All I have heard is our 8th plane is coming out of the paint shop soon and needs something to do. GTF is trained, has stairs, & mx. The 757 already does the PM flights, the station has been saying that they are getting the 757 on the AM flights starting in April.
Sorry, but I don't think those pairings are some part of a grand conspiracy, just wanted to be sure that those trips were covered by something (727) just in case there were any delays on the new plane. (Not like that has happened yet!)