Suburban Station Boarding Locations

SEPTA seems to be playing games with the boarding locations at Suburban these days. Push pulls originating at Suburban seem to be parking on track zero for some trains. The same train has been on five, six, seven and now zero in the last two weeks. This seems like a relatively new phenomenon to have push pulls boarding on zero.

Might as well use all the platforms right? Since no other operator is going to be running there

When that train comes over in the morning there's a bunch of trains in both directions, so it's easier to get them out of the way by clearing 20th Street and reversing them in on the 0. 7 track is where shops are placed if they need a swap from the good MUs on 5 or 6.