Why does my email A/B test inbox fine initially but then has deliverability issues after the winner is sent?

Email marketer from Email Geeks suggests that volume could be the issue, regardless of the A/B test split, as the total volume might be significantly higher than usual.

Email marketer from SendGrid shares that changes in content from the test to the winner can affect deliverability. If the winning email has elements that trigger spam filters (certain keywords, excessive links, etc.), it can cause issues even if the initial test passed. They suggest reviewing the content of the winning email for potential spam triggers.

Email marketer from Mailjet explains that inconsistencies in sending volume can negatively impact deliverability. If initial test sends are small and the 'winner' send is significantly larger, this sudden spike can trigger spam filters. Warming up your IP address gradually is crucial.

Email marketer from Constant Contact highlights that consistent sending patterns are key. If your A/B test is a one-off event and your regular sending volume is significantly different, this inconsistency can raise red flags with ISPs. Maintaining a steady sending cadence is crucial.

Email marketer from Validity shares that monitor feedback loops as complaints are delivered from the ISPs to the sending system, so you can monitor them, if there is a complaint spike after the 'winner' is sent, this can impact your reputation.

Email marketer from Email Geeks advises to investigate the time of day factor more, as different verticals and creatives can have varying optimal send times that significantly impact performance.

Email marketer from Email Geeks suggests looking into Google Postmaster Tools for domain reputation insights. Additionally, he proposes running A/B tests as full sends on different weeks to avoid time-of-day variables, or a seedlist testing service for inbox placement results.

Email marketer from Email Geeks suggests the volume might not be ideal for a dedicated IP, with a minimum of around 100k/day or 500k/week being a good target. Consistency and high engagement rates are also crucial, even for lower volume senders.

Email marketer from EmailToolTester explains that inconsistencies in test timing and frequency can skew results and impact deliverability. If the test is run at a different time than the full send, or if the interval between test and full send is too long, the data may not be accurate, leading to deliverability problems. Test under conditions similar to your regular sends.

Email marketer from Reddit suggests that the issue could be list quality degradation between the test and the full send. Even a small portion of spam traps or inactive addresses in the larger list can negatively impact deliverability. Regularly clean your email list.

Email marketer from Email Marketing Forum responds that it could be that your test environment doesn't fully represent live conditions. Spam filters often learn and adapt, so what passes initially may be flagged later. Use a seed list testing service that tests against real-world filters.

Email marketer from Litmus suggests that if the winner is sent at a significantly different time of day than the test send it could impact delivery, due to different user online behaviour at different times.

Email marketer from GlockApps shares that the content in the winning email could be triggering spam filters due to elements not present in the test emails. Run a content analysis using a tool like GlockApps to identify potential spam triggers.

Expert from Word to the Wise shares that potential cause may be due to sending the full 'winner' send using a different IP address. When testing ensure the IP you are using is the same as future sends.

Expert from Spam Resource explains that inadequate list segmentation might be the cause. The winning version might perform poorly with segments that weren't included in the initial A/B test, leading to lower engagement and deliverability issues. Ensure all segments are properly represented during testing.

Expert from Email Geeks asks if the timing (8am tests, noon remainder) and day of the week (weekday vs. weekend) are consistent, as these factors could influence deliverability.

Expert from Spam Resource explains that that a poorly managed seed list can falsely represent true deliverability. Check the seed list to ensure that seed accounts are active.

Expert from Spam Resource shares that a potential deliverability concern could be sending frequency. Have you changed your sending frequency recently? This impacts sender reputation.

Documentation from IETF explains that adherance to up to date email standards help prevent being flagged as spam. Ensuring your emails are properly formed with all necessary headers, and conforming to internet standards around DNS, SPF etc means your emails will not be flagged.

Documentation from RFC-Editor explains that inconsistent email authentication (SPF, DKIM, DMARC) can cause deliverability issues. Ensure that your email authentication settings are correctly configured for both test and full sends. Incorrect setup can lead to failed authentication and spam filtering.

Documentation from Google Postmaster Tools Help responds that sudden increases in email volume are a trigger for spam filters. Sending practices must be ramped up slowly, this is especially important for new IP addresses or domains. Maintain consistent sending volumes. Monitor your sender reputation using Postmaster Tools.

Documentation from Microsoft explains that sender reputation is a critical factor in deliverability. Fluctuations in sending volume or engagement can negatively impact your reputation. A sudden drop in open rates after the winner send suggests a possible reputation issue. Monitor your sender reputation with Microsoft SNDS.