Some of the piyutim in selichos assume that you're saying them at the ideal time - before Amud Hashachar (for example, at the end of selicha #70 שחרנוך קדם עמוד השחר). Many people don't make it at that time, and there are minyanim from the very bedieved 10PM until as late as 9AM. I've heard that R' Ovadya even suggested saying them before mincha if no time in the morning works, though I've never seen a minyan that does that.
A similar issue comes up during Neilah, with the line היום יפנה השמש יבא ויפנה. The Taz, Mishna Berurah, and others just say you should make sure to say it before sunset, but the Mattei Efrayim and Kaf Hachayim recommend that if you say it too late you should change the text to היום פנה השמש בא ופנה.
Is there a list anywhere of recommended changes to the selichos when saying them at a non-optimal time? It's very hard to come up with these on the fly.
The ideal list would:
- preserve the rhyme scheme, rhythm, acrostic, etc.
- give different options for 10PM, 6AM, 9AM, 5PM, etc. where that's relevant. (For example at 6AM in many places you could reasonably say שחרנוך עם עמוד השחר, like I did this morning, but that doesn't work at 9.)
but even a list of lines where this problem is relevant would be helpful so that I'm not caught off guard.
For me personally a list based on Artscroll's version of Minhag Lita would be best, but lists for other minhagim are welcome.