You will come to enjoy the sardine seating in Y (10 across on 777s), the angled seat in J and the loss of Gallery First lounge. So the least that the AF corporate manager is to provide you with status match. BA Gold is better than FB Plat in most respects, but they should match you to FB Plat (or at least FB Gold). When AF had a campaign of status matching anyone, they matched BA Gold to FB Plat. A limited number of such match is usually included in the contract when signed, but you should be insistent even if the quota is already filled.