I have upgraded about a dozen of routers with new bootloader and about 10 of them has been jammed after that. Don't do that if you want to upgrade your Mikrotik's from a distance... But what the h*ll? Those loaders are seemingly not intended to upgrade, since almos all routers will crash after that....

I upgraded my 951G from 6.28 to 6.30 and all my NAT rules were missing. The default one as well. Friend of mine did the same with Basebox and same result, however in this case rules were there but interfaces went to unknown state. This seems to be a quite big problem, since it's a suicide to upgrade...