I understand the problem but worry that the'll catch a chill can you protect them in any way outside eg fleece / cloches etc the wind still has an edge to it here and last night was the first without frost for ages, you could put them out in the day and bring in at night as the'll need hardening off anyway

Depends where you are I run a farm on the Chilten hills and my old man told me that you are not free of frost till the last full moon in May the theory has worked for the last 20 years! Fleece can work but don't let it touch the plant or the frost will bight through it.

Midden