Not that this will make you feel any better, but possibly those on your flight in club were being rebooked in club on the other flights - I imagine those in club may be a bit miffed if someone in economy was already booked in to the remining club seat and they were bumped to tomorrow.
I notice all remaining EDI-LHR flights are full now, they are all zeroed out, same for EDI-LCY flights. There is still space in economy on GLA-LHR flights tho if that's of use to you.
BA 1497
15/09/19 8:30
15/09/19 9:50
J1 C0 D0 R0 I0 Y1 B0 H0 K0 M0 L0 V0 N0 O0 Q0 S0 G1
BA 1493
15/09/19 9:20
15/09/19 10:35
J2 C2 D2 R0 I0 Y5 B1 H0 K0 M0 L0 V0 N0 O0 Q0 S0 G5
Status of your cancelled flight is
OPER so that is an operational issue. You should definitely put a claim in for compensation.
I suspect you may have had more success being rebooked on BE by an agent at the airport - those at the call centre can usually only rebook on oneworld at most. EDIT: although on checking all the BE flights are now zeroed out too.