Thanks for your post @crabby and welcome to our Community Forums.
We can set a rDNS to either the default setting of username.plus.com, static IP.plus.com or a domain name. For the third option, you'll need to create the A record first and we may ask for proof you own the domain.
Can you drop me a private message with your account username and which option you'd want your rDNS setting as?
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