I tried to find threads on these without success.

I am flying rt PHL-CDG 5Mar to 12Mar on an A332. This will be on the updated plane with economy plus section. I have 3 questions

1. PHL-CDG on 5 MAR is in J (upgrade just cleared). Does the A332 aircraft off load in the front or at the door between Business and Y?
2. CDG-PHL on 12 Mar is currently in Y. Is there a way to upgrade to Economy plus using miles + co-pay or is that only Y to Business?. E+ might be enough for a day flight. I can't seem to find the answer.
3. Any suggestions for seat choices in J with the aircraft that has economy plus?

I"ve done this flight several times, but only on 2-class planes.

Thanks in advance.