I garden in Savannah, Georgia zone 8a or 8b.
When I received some Billbergia nutans at our local swap they did not come with instructions. I planted them in the ground and they survived the winter with no problems. They were planted under some tall trees which created a slightly warmer micro-climate but that is all the protection they received. In the spring they grew, then bloomed and multiplied just fine.
After reading a bit about Billbergia nutans, now I bring one plant inside for the winder 'just in case'.