I grow my Spathoglottis in large pots under a live oak tree. I don't do anything to them in the winter and have about a 50% live/die ratio. They are cheap and I have bigger problems if we get very cold. They will take temps into the 30s but a freeze will kill them. You are further north than I so I would leave them in the greenhouse for the winter and yes, replant those bulbs.
Jim