Nope, totally wrong. Although BA lost its Carribean connections out of LGW and some western US detinations, move from LGW to LHR is only for the benefit of BA customers from Latvia.
In addition to this, wef winter schedule BA will move back to where it already once was timewise with early morning departures out of RIX arriving in LHR at 08:35 giving plenty of connections out of LHR + possibility to catch morning departures from LGW as well. Leave from RIX at 07:45 and arrive in JFK at already 09:35 on supersonic... Who else can do that???
Interested in more details? PM me!