Has anyone else noticed a significant increase in the time it takes for Exchange permissions such as Send As, Send on Behalf, and Read and manage (Full Access) to apply? In the past, changes in our environment usually took around 1–5 minutes. Over the last 3–5 months, that has increased to roughly 10–15 minutes, and more recently some changes have taken 20–40 minutes or longer. I understand that updates are queued and can be affected by service load, but the slowdown now seems unusually consistent. I'm looking for a sanity check to see whether others are seeing the same behavior.
3 Answers
There also seems to be a difference between the two admin interfaces. The main Microsoft 365 admin center warns that delegation changes can take up to an hour, while the Exchange admin center used to say they would apply in about five minutes. The longer delays appear to be affecting both now.
More generally, several Microsoft administration portals have felt slower and less reliable lately. Even basic searches in the Teams administration interface can require multiple attempts before the expected user appears, so this may be part of a broader service-side performance problem.
We’ve noticed the same thing. Delegation changes that used to apply within a few minutes are now often taking 30 minutes or more.

I remember the Exchange message saying “up to 5 minutes” as well. It would be useful to know whether that wording has officially changed or whether the estimate is simply no longer realistic.