What condition were they in when you got them, Shaun? And how much water have they gotten since then? Also, were they exposed to extreme cold at any point after purchase? If they came from a florist or indoor garden center, it is likely that they grew in a warm greenhouse, and were shocked severely when they came to your house. If they came mail order--not likely in that size--they may have suffered from conditions in the truck, on the way. Or, if they were in good health, and hardened off, they may have been allowed to dry out too much at some point. It sounds like the stems have died from freezing, "truck shock", or drought, and it is now trying to grow back from the stump. That is quite likely, but don't expect flowers in 2017.

If they had been in the garden all the leaves would have dropped off before now. Nothing you can do really except wait for Spring and harden them off gradually before planting out.

mail order here often send small shrubs/cuttings in 9-10 cm pots. I suspect they will be ok just keep them frost free until spring. They are unlikely to produce flowers though as they are very small.

Silly me! Shaun plainly stated 10 cm pots, and I immediately visualized 10 inch pots! There's a world of difference, I know! That may also explain the early basal growth, though I am slightly concerned that he makes no mention of buds breaking on the stem above.