Happy New Year Everyone

Wondering if you can give some guidance on my Visa queries:

1. I have a Non-Immigrant O-A visa with an expiry date of 4 Feb 22 with Multi-Entry. However, my Passport arrival stamp says up to 23 Feb. I assume the 23rd is the expiry date. Is that correct?

2.When I renew/extend my visa for a further 12 months do I also need to apply for Multi-Entry or is that automatic?

3. Assuming I satisfy all the criteria for the renewal/extension (30 days before the expiry date), how long does this normally take to be issued? (I'm planning to Thailand for a 6 week trip overseas on 31 Jan 22)

4. How long will it be before I can start to spend the 800k baht which has been maintained in a Thai Bank for around 6 months so far?

Thanking you in advance.