Dated and permalinked, which is rare. The catch is scope: these notes cover the API and Transactional (Mandrill). Changes to the marketing app itself are announced inside the product and in help articles with no date on them, which is why this column is short and old.
3 changes·verified 2 Aug 2026·read from Release notes
YoursNo platform does this for you. One concrete move, then you are done.FYIChanges a number you report or a risk you carry, not today's task list.SharedThe platform covers the mechanical bit. The judgement is still yours.
Announced
Yours
New Audiences endpoints put consent mapping back on the caller
What changed: Mailchimp released Audiences endpoints in beta as an alternative to List Members, so a contact can be created from an SMS number with no email address at all. The release note carries a condition in its own words: consent must be accurately mapped to the supported marketing consent values, and unsupported values, including opt-outs, must be updated manually.
Why it matters: That sentence is the whole entry. A migration that maps consent loosely is how unsubscribed people quietly reappear as subscribed, and this note is telling you in advance that the endpoint will not carry an opt-out across for you. Under CASL and under ePrivacy the burden of proving consent sits with the sender, and “the API did not support that value” is not a record of consent.
Do next: If anyone is loading contacts through these endpoints, ask what happens to a consent value the endpoint does not support. If the answer is that it is dropped, the opt-outs need their own pass before the first send, not after the first complaint.
Mailchimp began overwriting campaign_id and outreach_id on orders
What changed: Mailchimp started writing over the campaign_id and outreach_id values on orders to match its own attribution model and the account’s settings, and told integrations that send those values with Add Order or Update Order to deprecate that logic.
Why it matters: If you have ever tried to reconcile platform revenue against the shop’s own numbers and lost an afternoon, this is the shape of change that causes it. The platform, rather than your integration, now decides which message a purchase belongs to. Nothing about the emails changed. The number you report did, and it changed on a date.
Do next: Before comparing this year’s attributed revenue with last year’s, check whether the series crosses 6 December 2024. If it does, you are comparing two different attribution models and the trend line is telling you nothing.
Transactional sending domains had to publish DKIM and DMARC
What changed: Mailchimp told Transactional (Mandrill) users that from 15 March 2024 it would enforce new sending domain authentication requirements, citing the Google and Yahoo announcements. Two DKIM CNAMEs — mte1._domainkey and mte2._domainkey, pointing at dkim1.mandrillapp.com and dkim2.mandrillapp.com — plus a DMARC TXT record at _dmarc, for which the note gives the value v=DMARC1; p=none. Domains that did not comply would have their mail sent from a mandrillapp.com subdomain instead, with replies still routed to the original address.
Why it matters: This is the clearest example on the site of a platform doing the mechanical half and leaving the judgement. The record Mailchimp asks for is p=none, which is monitoring: it asks receivers to report and instructs them to reject nothing. A domain that followed this instruction to the letter and then stopped is authenticated as far as the platform is concerned and still unprotected against someone spoofing it. The fallback is worth knowing too — your mail keeps going out, but from a domain that is not yours, which is not what anyone reading the From line expects.
Do next: Read your own _dmarc record today. If it still says p=none and nobody is reading the reports, you completed the platform’s task and not the one that protects you.
Only changes that touch deliverability, consent, classification or a number you report are listed. Mailchimp ships far more than this; a builder getting a new toolbar is not a change to what is true about your programme. Missing something dated? corrections@emailrules.today.