We were in a Mega Rock Star suite in a few weeks ago on the Valiant Lady. You can go to the thermal suites anytime they are open (I thing their hours were 6am - midnight). But I recommend that you lower your expectations. I am a big spa going person and been in various thermal suites on different cruise lines. With our Virgin cruise, I only went once. It was such a disappointment that I didn't bother going again. No heated tile loungers and the steam and sauna rooms were just OK.