Is the online immigration appointment system in Thailand still available, and what is the current waiting time at Chaeng Watthana for a COVID visa extension?

AFAIK the online appointment booking system is still down (at least I can't access it :/)

Unfortunately the wait time is as long as it takes and I'm not being facetious :O I'm just telling you IF you're going today after the weekend there's no predicting how long you'll wait.

They started a new policy last week that they only let 10 people per section wait inside the immigration office in your section and every one else stays outside (still in building B though) until you are one of those 10 people in the section you need.