so you can tell if the train company you want to ride on is actually on strike below are names on strike.
While the strike is against 14 companies, there are actually 18 brand names you would be looking for because some companies run trains under different names (in parenthesis).
Scotrail in Scotland and Transport for Wales in Wales are not actually on strike. You may find their services busier because of folks using them instead of their usual company.
Check with strike page of the company you want to travel with. Fewer routes will be served and less frequently but on the 2nd some trains will run. Check before travel.
the train companies which will be on strike in the RMT strike on the 2nd of June are:
Avanti West Coast
c2c
Chiltern Railways
Cross Country Trains
East Midlands Railway
Greater Anglia
Great Western Railway (GWR)
GTR (including Southern, Great Northern, Thameslink and Gatwick Express)
LNER
Northern Trains
South Eastern
South Western Railway
Transpennine Express (newly operated by government but still old name so far)
West Midlands Trains (including West Midlands Railway and London Northwestern Railway)
so 14 companies but 18 brand names