It's not the time zones as I'm obviously here. It's the time
changes as Lou said. Not only is it difficult for whomever is manning the book but we also have shot-takers galore trying to take advantage of matches left up after they start. It's always been that way but now SBR is finally doing something about it. Tennis obviously isn't like other sports where the schedule is set. So we spend our time replying to PMs and posts, and not only grabbing the feed, but watching scorelines so we know when to pull the next match down.
If you desperately want to bet a match, PM Dax as Lou said.