I was flying that night and we diverted to LGW (at 2205 RVRs were 375m). I understand that all Cpts arriving at STN that evening have been phoned by FR management and asked to confirm the weather conditions when they landed.
EasyJet passengers were coached to STN; I listened to Swissport LGW read out a statement by FR that their pax would have to "make their own onward travel arrangements and contact customer service in the morning."
I'll remember that statement next time I think of booking with FR.