I just received two one segment upgrade certificates (BXP1).
I booked business class ticket (I) LAX-JFK-CDG-JFK-LAX.
I want to upgrade the transcon flights LAX-JFK-LAX by the BXP1 certs.

I'm looking at "How to redeem" in front of the cert, and it says
1. Make reservation for and purchase a published Economy Class fare ticket (except fares booked in B, N, O, Q, or S inventory) from your authorized Travel Agent or American Airlines.
Bold is mine.

So does that mean I can't use the BXP1 cert to upgrade my Business class seats to First class seats even A inventory is available