After a couple "no's" I talked to the supervisor.

She sent a message to yield management and the next day the seats were opened up.

A couple observations, I think it helped that this was the first segment. The supervisor could 'guess' these seats would eventually open up causing the RTW desk a lot of work in re-writing these hand tickets. This made me happy and made sense for AA [plus indirectly prompted me to buy an extra set of $10K in tickets not related to RTW today].

I am still unclear about the 'first flight' rule because the AAgent implied it could be changed until 7 days before the first flight which seems inconsistent with what is written.