No SQL support in mod_tombstones

When I start ejabberd 24.10 with mod_tombstones enabled I get the following warning:

`
Module mod_tombstones doesn't support database 'sql' defined in option 'default_db', using 'mnesia' as fallback`

Given that this seems rather important data to retain in the main SQL database I am wondering if it is planned to add SQL support.

Thanks!