One short devotion I do is the Devotion of the Three Hail Marys (catholictradition.org/Mary/three.htm), which is supposed to be prayed 2x per day. Sometimes, it comes to I pray the ‘day’ part just before sunset and the ‘night’ part just before sunrise–does this invalidate the Devotion?
Also, I just got back from Washington, DC yesterday (I was visiting the Franciscan Custody of the Holy Land’s American monastery) and I had to catch an early plane home (had to wake up at 4:00 AM on Monday morning). Anyway, I prayed the ‘night’ prayer for Sunday night/Monday pre-sunrise (although now my Scrupulous mind wonders if I actually did or not) and I think I prayed the Monday ‘day’/pre-sunset part. I was so tired, I sort of fell asleep on Monday night before I said the Monday ‘night’ part of the Devotion and woke up at ~8:30 AM on Tuesday (after sunrise). I quickly prayed the Monday ‘night’/Tuesday pre-dawn part of the prayer, but it was during the post-sunrise day of Tuesday. Did I now invalidate the promises of the Devotion of the Three Hail Marys?