For LHR Short haul
Ive seen that Jet 2, Euro Atlantic, Astreaus, Titan, Transavia, Viking,
I think its a mixture of 767,757,737 and A320 operating.
I think any route like to MAD or HEL where they codeshare with Iberia and Finnair respectively - only the non BA flights are operating.
Domestic looks to be completely cancelled at a quick first glance.
On a lot of routes it seems the earlier flights of the day are operating, a lot of routes are down to only one or two rotations.