Tim Watts wrote:

The only thing that's left on that linode is my primary DNS (zone, sub
zones and arpa zones for delegated reverse lookups).

Does anyone know of any DNS *hosting* company that provides support for
arbitrary arpa zone hosting?

My registrar gandi can't do it

I use gandi with AWS Route53, any particular type of RR you need to
support? I mainly use R53 due to its "ALIAS" feature like a CNAME to
handle web redirection to S3 buckets