I think part of the Gift Aid problem is that your tax status might change during the financial year in which you made your one-off gift, such that you thought you were going to be a qualifying taxpayer in May when you made the gift but were then made redundant and by the next April you hadn't earned enough to qualify.

I have never trusted my tax status enough to gift aid anything because I've been gig-economy between jobs. So this isn't definitive. But I don't need *more* things to think about if my income evaporates. This whole structure has been created by people who have never had to think about financial insecurity and who know that if their job evaporates their pals will give them a replacement one.