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  ## Key facts
  
- - Available on contact and lead records only. Customer Insights - Data customer profiles do not get a timeline.
- - Real-time marketing activity is shown for the past 90 days. That is a much tighter window than the 12 months used by journey, channel and contact insights.
+ - Available on contact and lead records. The timeline only shows interactions belonging to the record's own profile type — a contact's timeline carries that contact's interactions and nothing else.
+ - **Real-time marketing activity is shown for the past year (changed September 2026).** It used to be 90 days, which made the timeline noticeably tighter than the 12 months used by journey, channel and contact insights. The two now line up.
  - Interactions can be filtered in the control, so "show me every email this person opened" is a two-click operation.
  - On out-of-the-box contact and lead forms it works with no configuration. On custom forms you have to add a custom connector to the timeline component in the Power Apps maker portal, with constructor `msdynmkt_DynamicsMktTimelineInteractionAnalytics.TimelineInteractionAnalyticsResource` and resource path `msdynmkt_DynamicsMktTimelineInteractionAnalytics`, then save and publish.
  - Read privileges are needed on the underlying tables for anything to appear: `msdyncrm_marketingemail`, `msdynmkt_email`, `msdynmkt_sms`, `msdynmkt_pushnotification`, `msdyncrm_marketingform`, `msdynmkt_marketingform`, `msevtmgt_event` and `msdyncrm_website`.
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  - Whether to enable exact copies of sent emails, with a data protection sign-off, knowing the one-year retention and the no-backfill rule.
  - Which security roles get read access to the eight interaction tables. This is where most "the timeline is empty" tickets come from.
  - Whether any downstream process needs the email retrieval API, in which case Fabric integration is a prerequisite for getting the GUIDs.
- - Whether the 90-day window is enough for the sales conversation, or whether the team needs a Power BI page over the interaction data instead.
+ - Whether a year of history is enough for the sales conversation, or whether the team needs a Power BI page over the interaction data instead. This is a much easier conversation than it was under the old 90-day window.
  
  ## Gotchas
  
- - The 90-day window is the single biggest surprise. Users assume the timeline matches the 12 months they see in insights, and it does not.
+ - The old 90-day window was the single biggest surprise on this feature and it is now gone. If you have written it into a design document, a training deck or a set of UAT scripts, go and correct them — telling users they only get 90 days when they get a year is the kind of stale advice that survives for years.
  - Custom forms show nothing at all until the connector is added. It fails silently — no error, just an absent section — so it survives UAT easily.
  - Missing read privileges produce the same silent emptiness. Two different root causes, one symptom, and both look like "the feature doesn't work".
  - Exact copies only exist from the moment the feature switch is enabled. Turning it on the week before an audit gives you nothing for the period being audited.
- - The timeline does not cover Customer Insights - Data profiles, which catches out projects where the audience source was set to customer profiles rather than contacts.
+ - Microsoft removed the explicit "no customer profiles" limitation from the documentation in September 2026 without replacing it with a positive statement of support. Until the docs say customer profiles are covered, treat the timeline as a contact and lead feature and don't scope work against Customer Insights - Data profiles on the strength of a deleted sentence.
  - Rendered email copies age out at one year, so any evidence retention requirement longer than that needs an external archive rather than this feature.
  - Adding the connector requires publishing the form, which on a customised environment means a solution deployment, not a five-minute change in production.
  
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  ---
  
- *Worth another look if the 90-day timeline window changes, or if Microsoft extends interaction timelines to Customer Insights - Data profiles.*
+ *Retention moved to one year in September 2026. Worth another look if Microsoft states positively that interaction timelines cover Customer Insights - Data profiles.*