As if it wasn't complicated to understand until now, let's make it even more complicated
Example A though still shows how the most frequent flyers still don't get anything, would it have been so complicated to just add +1 year of the same level and not touch the XP at all (not add nor offset anything at the end of the membership year).
Example E is also interesting, PAX had 75XP in Jan 2020 and somehow managed to lose 5 of them by Dec