Don't fall prey to the 'sunk cost fallacy'. That past is written in stone, but from the present point forward, the best course of action is the best course of action, regardless of what you've invested to get to this point.

So, from here forward, are you better off staying with Piedmont, or going somewhere else?

I'm not saying you should or shouldn't leave, but don't let sunk cost taint your decision.

FWIW, it took three months to get from the start of my first sim session to completion of OE and (finally) a line pilot. That was all training delays. My sim partner and I passed every lesson and ride on the first try, and completed OE at the minimum required hours.

So, even though you've been on the Piedmont payroll for half a year, your quickest route to being a line pilot is probably still not Piedmont. Pathetic, isn't it?