on a pool of 50 people some people receive the alert after 8 minutes, others after one hour. It wasn't like that some months ago, but the timing gets worse.
The alerts are set on an announcement list that has an average of 2 announcements per week.
The alerts have been set MANUALLY for everybody.
Is the problem in SP and where do I have to look? is it in Exchange?
SP on premise 2013, exchange server 2010 on premise