Cobham have made no secret of the fact they don't want to be seen coming out or going into a military airfield so I can't see them moving to Leeming, especially since Leeming's future isn't all that much better than DTVAs.
What worries me is despite them moving out for Winter, if they find operating out of Bournemouth / Newcastle is easier than they anticipated, what's to stop them from not coming back?