Keep on waiting.
If you get a frost warning, cover your plants with some sheets or painter's drop tarps to keep the dew off of it, then uncover them in the morning.
Cannabis plants are mighty resilient. I'm in zone 5 and had to fend off frosts two nights now, over the past week. My plants still have a couple weeks, so I'm rolling with the blows and trying to keep them comfortable until they're done.
I hope this helps.