From what I have seen, Peel have encouraged a few companies to try out other airports in the group.
Existing KL flights from MME, may have helped LPL get KL, also GSM moved from LPL to MME, dropping flights from LPL to TFS etc to open a base there.
Also TOM had a small base in LPL until DSA came along.
BE although not having a base in LPL moved from LPL to MAN, but flights in LPL remained and others were opened up from DSA
Jack