As far as I understand, Bronson are a bit like RMC and some other Japanese operations, they do seasonal batches. It also depends on how popular the items are, like the hugely popular Tankers and N-1. they are having improved models in 3-4years running. I would say they restock things once per season.
P.S. Better wait until their coronavirus outbreak to die off, WuHan seems to be the transport hub in China, and it is shut down, there will be no flow of goods at all in most parts of China.