For Microsoft 365 contacts (the contact's email matches a connected Microsoft 365 user in your CRM), out-of-office status is surfaced as a small badge on the contact detail panel and in the email composer's recipient field.

We read this from Microsoft Graph's MailboxSettings.Read scope, which is granted at Microsoft 365 connection time. Status is cached for 1 hour to avoid excessive API traffic, then re-fetched on demand.