Accourding to the documentation for JSON DOH queries, record type can be “either a numeric value or text”. However, for example, when using record type 28 (per RFC 3596) instead of “AAAA” I’m getting back A-record anyway. In this example taken from the documentation the first query returns ipv6 address as expected, but the second one returns ipv4:
Other DOH resolvers I tested don’t have this issue. This is also reproducible with other record types (such as 15 for MX).
Thank you for looking into this.