Theoretically the window for the next round is open when the previous round is concluded and we know all the fixtures.
In reality the might be some waiting time while I sort out the website and open up the link to the new prediction page.
Today that wait will be like 10 minutes because I’m up until 5am, watching the football. For other rounds, it might take a few hours. But there’s always a day or two break between rounds, so you have plenty of time. Just keep checking the link.