Is that on the Thurday night (22'nd Feb) BA 57? There is certainly 27 AB and JK on my seat map in MMB and what's more, the seats are available for selection. Something stange is definately going on here. Just noticed, the galley around row 40 also seems to have moved??
Is there any possibility that I'm looking at G-BNLU (the first low J fo be converted). Very unlikely but perhaps they have tinkered with WT- whilst they were at it?