iCloud+ Custom Domain question about DNS

I'm currently self-hosting email on a NAS with a static IP and would like to switch to using iCloud for this (it's less hassle due to all of the security issues with email server hacking and unwanted server exploit scanning attempts on my IP from companies like Stretchoid). Should I ask my ISP to remove the Reverse-DNS record (PTR record) for it to work well with iCloud or will that matter at all? I'll still be modifying the rest of the DNS records according to Apple's documentation.