Ping the website(s) and do a tracert. It's still up, but the html is not populating. That's usually indicative of an 'admin down' situation which the timing supports (starting a bit after midnight Beijing time and rolling into a weekend).
I'd expect the sites to come up no later than Monday (8am or earlier - Beijing time). That is when a "maintenance window" would typically end in the IT world.
Yes, taking a whole weekend would be weird - but not if you websites are undergoing an overhaul/revamp/etc.