I've recently contacted Marlin and he says that although there have been some V4's released they've been in very limited numbers. Therefore, Marlin currently has a waiting list going that's probably growing by the day. If you're interested in getting quite possibly the best 127 (outside of getting a gen) I'd recommend getting on that list ASAP.
Under normal circumstances Marlin's turnaround is 1-2 weeks however with China being out of stock, it's going to be a fair bit longer I think.
I'm just using this time to save up for one of Marlin's awesome 127's. Can't wait....