This is precisely what we have - 1 subscription group with 4 plans:
1 Advanced monthly
1 Advanced yearly
2 Basic monthly
2 Basic yearly
So I want to know when a user changes their plan
from Basic Monthly to Advanced Monthly (upgrade)
from Advanced Monthly to Basic Yearly (downgrade)
from Advanced Monthly to Advanced Yearly (crossgrade)
With this setup, should I have isUpgraded == true in case of an upgrade? How in the code can I figure out other scenarios?