The possibility of Google applying SPF checks to EHLO values for stricter email authentication is debated. There are reports of Google tightening authentication requirements, leading to speculation about increased scrutiny of EHLO values and FcrDNS. The SPF specification mandates checking EHLO before MAIL FROM, but implementations vary. An authentication issue to be aware of is the PTR record showing a hostname that results in NXDomain, potentially impacting deliverability. In the age of DMARC, SPF HELO checks are becoming more relevant due to domain alignment requirements. While MAIL FROM remains the primary focus, HELO/EHLO checks can still impact deliverability, and a valid, resolvable hostname in HELO is crucial.