I agree with TomS that since you said you need the appraisal to make the credit decision that your clock (probably) doesn't start until you get the appraisal back.
That said, this is a tricky area as Reg B isn't abundantly clear on when the clock starts and, in fact, leaves the definition of application wide open for financial institutions to have different definitions of a completed application. As some auditors and/or examiners don't always see things the same way, some financial institutions just provide a conditional approval in order to avoid any discussions about the 30-day rule.
Again, this is a complicated topic, but if you are interested in more info on this, here is an article that explains my take on this:
https://www.compliancecohort.com/blog/regulation-b-30-day-rule.
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Adam Witmer, CRCM
All statements are my opinion, not those of my employer, and should not be taken as legal advice.
www.compliancecohort.com