The A319s are already operated by a different company, EUROWINGS Flug GmbH, as opposed to EUROWINGS Luftverkehrs GmbH, which operate the rest (ATR, CRJ and BAe).
I don't work there, but I suspect that there is no seniority based upgrading system.
There have been rumours about Condor Berlin and Eurowings A319 merging, by the way...