I entered last year, and plan to enter again this year.
The thing is, the novel I entered last time has had so much work it is much better, and hardly recognisable as the previous entry. As far as I can see, there is nothing about re-entering a book.
I do have another novel almost ready to go. I personally think it is the better of the two, with more depth and more action. But it is a follow-on to the previous one, and may suffer from that.
What do you think?