UPDATED: How crazy did deliverability get during AOL’s migration? We investigate.

UPDATE: Shortly after publishing our findings on the AOL migration, a mail product lead at Oath mail advised, “the migration is not yet complete.” At 250ok, we’ve been monitoring the MX records for AOL.com and the associated domains, which transitioned several times between the previous AOL infrastructure and the new infrastructure at Yahoo. Our below data and review summarizes this period of the transition, as it is the portion that caused the largest impact to email marketing to date. 

Stay up-to-date with the ongoing changes at AOL and Oath by subscribing to their blogs, postmaster-blog.aol.com and oath-postmaster.tumblr.com.

You may recall on January 29th we discussed the upcoming changes to mail systems that manage email on behalf of AOL.com and their associated consumer domains. The team at 250ok monitored the migration from start to finish, which ran for the entire month of February, and now we are ready to share what happened to email delivery during the migration.

Are you ready? Ok, here we go.

A week-over-week view of the migration shows the weekly average Inbox Placement Rate (IPR) drop noticeably, to the tune of almost 10%, during the migration.

We also monitored a corresponding increase in missing mail sent to AOL while the majority of migration testing, change rollouts, and rollbacks were occurring. These results coincide with several reports of higher-than-normal bounces, mail queuing for delivery, messages delivering without actually arriving, and users reporting being unable to access, send, or receive emails.

Week-over-week metrics:

During the transition, we monitored the worst day average at 66% inboxing, with a 20% missing date the same day. IPRs have since rebounded as the majority of the migration is complete, and they’ve returned to the pre-migration range of 75-82%.

While AOL’s postmaster team has yet to announce the migration completion on their blog, we monitored the new MXs and they have been stable for the last week. They are no longer changing back and forth between the new and old email infrastructure, which makes us confident the most significant changes in this regard are complete.

90-day view of AOL Inbox Placement rates:

Still having issues with AOL Delivery? Be sure to reach out to your 250ok account or sales representative for information on how we can assist in getting your IPRs up and more mail to your subscribers.

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