Am taking chances with the tomatoes and putting them into the 4TB. They will be nestled within fleece, this will hopefully protect them whilst allowing them grow a bit more hardy. I know that they are still quite small, and we may still get a frost. The 4TB does however get quite warm at the moment. Have just taken out a tray of squashes and cukes, they were wonderfully warm. There are still three very tiny tomato babies still being held in side. Will keep an eye on the 4TB over the next few days, just in case.