Need to extend my 60 day tourist Visa by 30 days can I go to any immigration office? I am staying in Bang Khae but want to go to Nothaburi as CW is closed.

You can use any immigration office but normally they want to see an address on the TM7 with an address within their jurisdiction.

There are two temporary offices open. See: Immigration services at Cheang Wattana now suspended

I also have a double-entry tourist visa and am currently using the first one. My initial 60 days are up next Wed. Can I go before Wed to apply for extension for extra 30 days? And the 30 days would start on the day the 60 days expires (Wed) -- and not on the day that I apply for the extension, is that correct?

In fact, can I apply for the extension at any time during the initial 60 days?

I am sure this has been answered previously in this forum, but I could not find it and apologize beforehand.

Thank you for your help.

You cna apply during the last 30 days of your 60 days permission to stay and it will start at the end of the 60 days.

Keep the validity of the visa in mind, you must make the second entry before the visa itself expires!