Hi Phil1
It is possible that a hog hasn’t come out of hibernation yet. It isn’t completely temperature related and they have to go through the process of coming out of hibernation which may take some time. I know the advice is not to clean out boxes until April, but I find here, that the females don’t tend to return until at least mid April. Some of the hogs went to hibernate quite late, and so may return later. The older females here, have not returned yet. We have to remember that there was also the cold snap before the warm weather and I found the males returned later than usual.
I think it is too early for babies yet. Although, I suppose if a male and female both didn’t hibernate, it may be possible, if unlikely.
A hog could just be using it as a day nest. To be sure whether a hog is going in and out, you could leave some rolled up paper or a small twig in the entrance and see if it has been disturbed. I find hogs are very clever at going in and out of boxes without us seeing, even if we think we have been watching all the time!
