Verified via DoH: _dmarc.axion1337.de is p=reject (sorb changed it), subdomains
inherit reject with sp= absent per RFC 7489, and the noted DKIM gap was a false
alarm — IONOS uses s1-ionos/s2-ionos/s42582890 selectors, all present with valid
keys. Apex SPF left at ~all deliberately: real mail flows over the apex and DMARC
already enforces reject, so -all adds little while risking silent send breakage.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>