In order to understand the various answers you may see to this question these days, it's imperative you understand their background.
The basic law is to read the Torah sequentially, but occasionally the sequence is interrupted (such as on Yom Tov). All other breaking points are entirely customary.
Historically some communities read sequentially to finish the Torah every 3 or so years, and others read to finish every year. The latter one is the widespread custom nowadays.
Most people don't realize this, but there were dozens of different customs medieval communities had for how to split the Torah up to finish it each year (this isn't the place to list them all, but here's but one relatively famous one). We have records of some communities switching to different practices for various reasons. Most of these are no longer practiced, but there are still a few different customs out there nowadays. None is halakhically fundamentally better than any other; they are just different customs. There is no, as you say, "universal cycle". This is surprising to many, but is explicit in Rishonim. The Rosh famously said (Chazeh HaTenufah 54):
חילוק הסדרים וחיבוריהם הוא כדי שתעלה קריאת כל התורה בשנה אחת ולכן כל חכם בעירו או בארצו חיבר והפריד הסדרים כפי הסדר שראה שהוא הנאות ואין הסדור ההוא הלכה קבועה רק מנהג ואינו חובה
The division of the sections and their combinations are in order that the whole Torah will be read in one year, therefore every wise man in his city or his country joined and divided the sections according to the order he saw fit, and this order is not a fixed law but a custom and is not obligatory.
Based on this perspective, which was probably well understood by anyone who lived among such varied practices, Or Zarua (2:45) records that when someone in his synagogue prevented the community from praying together one Shabbat and reading Emor, they should read Emor with Behar the next week because the goal is to read the whole Torah each year and it doesn't really matter how you split and double things up. It's no different from some other town's custom or from when a regular Shabbat reading is superseded by a holiday. This was followed as well by Mahari Weill to read Naso with Beha'alotkha after the community was shut down temporarily by the local Christians. This ruling was summarized in a much more popular halakhic work at the time, the Aguda, briefly as follows: if on Shabbat they were unable to [perform the] regular service and they didn't read the section, they should read the section the next week [making] two sections.
Maharam Mintz (85) was later asked about a somewhat similar case where two members of the community fought for hours about which deserved the final Aliya of Vayakhel-Pekudei. They fought for so long that most everyone else left and finished the reading in a different building. The question was the next week if the main synagogue needs to reread Vayakhel and Pekudei along with Vayikra in accordance with the ruling of the Or Zarua because there was an interruption before the members finished up elsewhere. He rules that there is no issue of interruption and that moreover the Aguda explicitly said "two sections", which [apparently] implies not three sections, so reading Vayakhel-Pekudei-Vayikra would be too much. Additionally he suggests that it would be impossible here because these sections are in different books and the custom is to say "Chazak" after a book and to join the multiple sections in one overlap Aliyah.
These arguments are unprecedented and are being used to buttress an essentially obvious conclusion that the whole synagogue doesn't need to read two whole sections again for two rich guys who caused a fuss. It's also readily apparent from his wording that Maharam Mintz was only working with the summary in the Aguda because the Or Zarua himself says nothing about reading only two sections (this is noted already by Zikhron Yehonatan OC 2). It's true that ordinarily there's no need to triple up on sections to make the calendar work, but the whole argument of the Or Zarua is that any breaks are fine as long as you finish on time, while Maharam appears to think there are specific sections assigned (by whom?) to each week. Additionally, we know the Kohein Gadol could read from two books at once (Yoma 70) and the Tosefta (Megilla 3) says that one can read from the end of one book to the beginning of the next as long as you have 7 readers in at least one book. Finally it's hard to believe Maharam really intended his argument to stand on its own since the practice of saying "Chazak" and having an overlap Aliya are clearly just customs whose absence wouldn't invalidate the reading.
While Maharil ruled against reading missed sections lest someone get confused about when the next Yom Tov is, and we can imagine other Rishonim who didn't comment may have felt messing with your regularly scheduled breaks isn't worth it, Rama (OC 135:2) rules like Or Zarua that it is worth messing with your regularly scheduled breaks to still manage to read it all annually.
Some Acharonim quote Maharam Mintz's restrictions approvingly (Magen Avraham, Keneset Hagedolah, Olat Tamid, Noda Bihuda, Ateret Zekeinim, Shulchan Atzei Shittim, Maseit Moshe, Chokhmat Shelomo, Solet Belula, Shaarei Ephraim) but most rejected his novel position (Haghot Minhagim, Eliya Rabba, Bigdei Yesha, Beit David, Shathilei Zeithim, Maharam Shik, Chida, Matteh Yehuda, R' Nathan Adler, Peri Chadash, Devar Moshe, Ikkarei Hadat, Shulchan Hatahor, Noheig Katzon Yosef, Emet Leyaakov, R' Yehuda Miller, Birkhot Mayim, Zikhron Yehonatan, Yerekh Yaakov, Zekhor Leavraham, Hillel Omer, Betzel Hachokhma, Arukh Hashulchan). Notably, nearly all the authorities here who wrote about actual cases where Maharam's opinion would matter are in the latter group.
For our case, it's important to note the opinion of the Sha'arei Ephraim (who himself accepted Maharam Mintz's position) that Rama's ruling only applies when the community prayed together and became obligated to read Torah but had to disband before reading it; only then is there a latent obligation to deal with the next week. This is a novel theoretical position perhaps based along with Maharam in a notion that each week has an assigned (by whom?) section to be read, but historically it doesn't seem to have been followed as most cases in the literature of this law being invoked are clearly where the synagogue was closed entirely that week, generally because of persecution or extreme weather (Mahari Weill, Noda Bihuda, R' Yehuda Miller, Zekhor Leavraham, Breikhot Mayim, Hillel Omer, Yerekh Yaakov above, as well as Leket Yosher, R' Chaim Palagi, Chida, Shevut Yaakov, Mekor Yisrael, Mattat Yad and Teshurat Shai; even in the Or Zarua's original case they didn't pray together). I don't know of a single actual case historically where a rabbi ruled for an actual community like the Sha'arei Ephraim; maybe someone here does and can comment, but it is certainly a minority if not solitary opinion that wasn't quoted by any later major codifiers (not even treatises, like Mishna Berura, that regularly quote the Sha'arei Ephraim). Notably, the Sha'arei Ephraim and many others admit that even if not obligated to, one could choose to read all the missed weeks' sections since we can add Aliyot on Shabbat. Thus even if you view this dispute as a full blown doubt, there is probably a way out.
(A few small notes. 1) All this discussion surrounds communities. Individuals who miss Torah reading are generally assumed to not be obligated to find a way to hear it. Whether one synagogue being open in the country somewhere counts to make everyone else in the category of exempt individuals seems highly unlikely, though it's hard to prove it. How to account for every different minyan in a city is difficult. 2) The Vilna Gaon alludes to the laws of Tashlumin for prayer in regards this rule leading some later authorities to posit a third position here that one can only make up the most recent weeks' worth of sections and only if they were missed by accident and by reading the newer section first, all like Tashlumin for prayer. This would be a brand new position with no source and is contradicted by his own practice reading sections from four weeks to catch up after being released from prison. Interesting conceptually and food for an entire Shiur, but difficult to do anything with practically. 3) The special readings of the "Four Parshiyot" do not follow these rules since they don't fit the Or Zarua's logic. Some believe they can be made up when still thematically appropriate to the calendar.)
Clearly the main position here (by any standard: historically speaking, simplest logic, majority of early opinions, majority of later opinions, majority of implemented cases) is like the Or Zarua said that this is all a custom so you can read as much as you want. And having every community finish the Torah every year is obviously a positive value. But by the same token since it's just a custom, when extremely burdensome to a community one could imagine (as did Zera Emet 3:14 regarding a town that lacked a qualified Torah reader for months) skipping out on the custom to finish the Torah one year, whether because of Kavod Haberiyot or because בזה לא נהגו the custom was never meant to include such extreme situations (the minority opinions of Maharam and Shaarei Ephraim could be offered as snifim lehakel in such circumstances). Every community needs to figure out what is feasible for them while keeping everyone safe, whether that'll be reading everything, reading just what's in the current book, reading just the last two, reading them all just at one early minyan for a small representative sub-tzibbur (since this is a communal obligation, not an individual one), or perhaps reading the missed sections outside the regular service over a few weeks as a token symbolic gesture towards how much we missed our Torah scrolls. (Remember too that an extra few hours once in the next month is still significantly less than the amount of time you would have spent in shul the last few months.)
What is abundantly clear if you read all the above sources inside is the love and desire these sages and communities felt about hearing all the Torah readings, the lengths they went to try to accomplish that and the dismay they felt when unable to. Any ruling on this question must be rooted in that perspective and then work to deal with the challenges in any given community. To just say "there are some doubts here since this is a rare question so better to just do nothing" is not the way any of the above sages approached this question, with each lengthy responsum after the next showing how much its author cared about figuring out what to do for his community in his case. It's possible many Jews this year will be forced to not take part in this time-honored and beloved practice of reading the whole Torah each year, like many other beautiful Jewish practices which have been skipped or minimized this year, not because the imperative never existed but because in Judaism saving lives is obviously more important.