Some email servers 'stamp' the email with the time at the server, others leave the time set to that included from the sending platform. So the emails that 'appear' to be taking many hours to arrive may, possibly, not be taking so long; it may well depend where the email server that processed the email is based. In addition, if you look at the email source (you can't do this on the iPad but if you have a PC there you can 'dig down' into the email and see the underlying 'source'), you'll be able to see not only the real time at which it was sent, but also the time at all of the various intermediate relay points along the route from source to destination.
Furthermore, some servers that aren't so busy don't forward emails immediately but 'gather them up' into a reasonably sized 'batch' before forwarding them. I know that you're based in a fairly remote location and I wouldn't be surprised if this wasn't happening to you. To complicate matters even further, if the receiving email server cannot be contacted when the sending server tries to deliver the email, the sending server will try again later and the interval between attempts can be many hours.
I hope you're still enjoying your time there....
Tim
