BB Software :: Emails Stop Coming In Every Afternoon?

This is very strange, for the past few weeks now my device stops receiving emails in the afternoons. Sometimes it's from noon-11pm, other times it's a few hours say from 2pm-5pm. I just can't get my head around it. I'm still collecting mail in my PC inbox but it's not getting pushed to my device and they all come in at once later on. This is just a regular pop mail account like mail.mydomain.com. I've had the same host for years without problem and a blackberry for about 5. It's a blackberry bold 9000 (I've had since Jan 09) and on the Rogers network in Canada.