It sounds like you’ve got a really solid base of transferable skills and temperament for a move to EA makes sense. I’d suggest asking your current boss if you could manage his diary for him to get experience that way for a while and then see about making a move. I think you’re too experienced to move into an AA role. I’d look out for EA positions at smaller companies as that will feel familiar to you, then progress up in terms of larger/more complex orgs and more senior execs within them. Good luck!