Replacing a module with a better one is by definition a module upgrade, no matter what’s the reason behind it. And don’t worry, I know that thread by heart (like almost every thread in the forum ;)). If you have any doubts about that just take a look at my forum stats. 
So back on topic, here are the upgrade stats for all modules:
- Cover
- upgraded
(to make up for a major flaw) - Camera
- Upgrade announced to come soon!
- Top Module
- Upgrade announced to come soon! (along with the camera upgrade the front camera will be upgraded too)
- Main Module
- minor changes made as seen here.
- major upgrade very unlikely.
- Screen
- Minor changes made (mainly due to changed supplier) - whether bright spots are fixed by that remains to be seen.
- Bottom Module
- no upgrade announced (personally I guess this will be the next module FP will try to upgrade, because besides the screen it’s the module most prone to hardware issues).