I have checked the syntax of my SPF and DKIM DNS records on multiple different services... everything checks out OK... but I still get a large red question mark beside emails sent to gmail.com because they claim that the IP address I am sending my mail from is not permitted or denied by my DNS records.

What gives?

I just setup the DNS records 24 hours ago, but everything has fully propagated to all of the free online checkers I double-checked with... so surely google has the correct DNS settings by now?