Most junior pilots in base as of December 2015:

CMH: New hire
DCA: 5/11/15
EWR: New hire
GSO: 6/30/15 (10 FOs in the base)
IND: 9/9/15
LGA: New hire
MCI: 10/20/15
MIA: 6/30/15
ORD: 6/9/15
PHL: 6/30/15
PIT: New hire