I have 2 future AY bookings, both with a combination of AY, BA and SU flights in them.

I can see the same thing. The AY operated flights in the bookings (HEL-SVO, and HEL-ARN) are both showing 3 x 3 seating. Very strange.

I will be passing back through HEL this Tuesday, so I'll be able to tell you then if this is something new, or if AY have their own IT problems.