Offline email on the ipad

Hi - apologies if i have missed a thread. I have a WiFi Ipad and its a great platoform to read emails on. Like many "professionals" i find it extremely useful to handle my emails offline (no wifi) eg when on the move. I have an exchange account but this does not handle offline email. On advice from Apple and our IT team i switched my ipad email to an IMAP platform. This allows me to read emails in my in box when not connected BUT any edits i make (deletions or moves to other folders) are NOT transmitted to my exchange accountn when i go back online. This means that i may spend hours offline editing my inbox but end up having none of this transmitted to my exchange server account ie its largely a waste of time. Both our (highly qualified University) IT team and Apple Support seem to have run out of ideas.
Surely thousands of professionals have hit this problem by now? For me, having no offline (cached) email on the ipad makes it drammatically less useful.
Any suggestions hugely welcome (I have tried nearly everything).