I grow Bletilla Striata in zone 6 New Jersey. I've seen Ochrea listed as zone 7 and zone 6 so i think they are a little less hardy.

I wouldn't disturb them now, if they died over the winter there is nothing you do now, if they are alive you might kill them by digging them up. They should sprout in a few months, mine do in late April - early May. In the fall I pile a few inches of shredded leaves on top of the bed for protection and to amend the soil. A late spring frost will damage the new growth and flower spike so I try to keep the leaves there until late spring. My wife on the other hand likes to clean out the beds on the first warm weekend.

Supposedly they're slower growers than Bletilla Striata. It had a nice root system from what I could see in the pot. I think I misspelled Ochrea too. The flower is supposed to be yellow or pale yellow.