There is custom (Minhag) to eat Matza at Shavuos and Rosh Hashana. (Here is the source) based on the Kolbo and also in found in the book Shmo Yosef. My question is at what meal to eat the Matza (at the evening meal or at the morning meal or both) in both Moadim: Shavuot and Rosh Hashana? In addition, does the Matzah has to be a residual Afikoman that was kept or any Matzah can be used for this custom (minhag)?
The Kolbo brings it as a follow-up to the minhag of eating dairy, so possibly it would also apply to the day meal (or whatever minhag you follow for dairy). What makes you think it would have to be from the afikoman?– shmoselMay 24 at 6:56