When I recently transferred my email server from windows to linux, I initially moved some domains individually as a test, then moved the rest in a batch. Every one of the domains had an spf record that included a:mail.mydomain.com. Each of the mail.mydomain.com was a cname record back to my email server, mymailserver.com. Thus there was no change necessary for the spf records for this move. With the new version of SmarterMail and it's dynamic certificate management, I am having all of my customers use their own domain name settings for email configuration and webmail access, rather than have them all point imap and smtp to mymailserver.com like I used to. This configuration makes it easier for me to move clients in batches in the future (something I learned last week when I did my transfer). As for dmarc, I have all of my dmarc records point to a single reporting email address that accumulates reports, so no change necessary for that.

So, I think the answer depends on how your SPF records are currently configured, but my suggestion is to make sure they all cname back to your email server a record so that you can change the IP address on that record. I would change the TTL on that record to something very low (I use 60 seconds) when doing the transfer.