Do I need to visit the main immigration office for my extension, and is the registration form required?

Hello.

The question about covid extension.

I had student visa before, so I got my extension with embassy letter till November 30. I did it in the main immigration office in Bangkok (not temporary one).

So my question is: should I go to the main office again or this time to the temporary one?

And the second thing: is the registration form required?

So should book a time for registration address first, then for extension? Or is it fine to go straight for extension with copy of the contract? (Cause getting all required documents from the landlord is kind of challenging...)

Thank you