There's a further update that LGW is staying closed for the time being, and the diverted flights are no longer showing an onward route to LGW. Well, one exception the NCE flight still has a Stansted link. My guess is that BA will disembark all passengers at STN and LHR now. Affected aircraft are
- BA2625 NCE - diverted to STN
- BA2709 BCN - diverted to LHR
- BA2965 GLA - diverted to LHR
- BA2977 SVQ - diverted to STN
and the Venice flight has been stopped overnight in VCE
Easyjet has a lot more flights affected, and they've got a stack of aircraft arriving into LTN.
BBC news report confirming the story, and diversions tweets
https://www.bbc.co.uk/news/uk-england-sussex-46623754