Hot off the presses:
They literally did not have reserves for FOs in DCA for March. I suspect the company will handle this with all the new FOs that will get dumped there fresh out of training before they're able to bid.
R1 = Round 1 Award. Bid a line, then SAP to your hearts content. Your final line could look nothing like what you were actually awarded.
BU = Build Up line. Leftovers in Open Time after the SAP. Not a lot of flexibility, but you'll know your schedule in advance.
LCR = Long Call Reserve. 12 hour callout.
SCR = Short Call Reserve. 2 hour callout, 1 in TYS. Can be converted to Hot Reserve a few times a month.