I'm pretty sure that I read somewhere that BE are the third largest slot holder at LGW after BA and EZY so I can't imagine it would be good business sense for LGW to loose them.
Also, you have to remember that BE have served LGW for many years and their routes are only now becoming inefficient due to the revised charges imposed at LGW, but maybe that's just business.
It's just a shame that domestic routes once forced out of LHR may also now find the same fate at LGW.