Exactly! And as we have seen in the past, the company will use external recruitment (eg, WW temps) as a way to work through the transfer lists while keeping the operation going.
I wouldn't be surprised if, once the holding pools have been depleted, we see external temps going into 'mid fleet' and then being offered LGW as LGW achieve their LHR transfers. Then again, you know what the company is like - anything can happen.