is turning email updates off between a specific time possible?

It was an option on my Treo, but sadly not on the iPhone.

Perhaps some of the fanboys can chime in and tell you why you don't need that option?

 

Well, duh. Apple didn't expect people to sleep.

 

You can set e-mail updates to "manual" in the settings. Or you could turn your phone off, or put it in "Airport Mode", which will prevent it from receiving any e-mails, text messages or phone calls.

 

Mine are so quiet, I can have them go off a hundred times at night and not hear them.

But you do raise a good point. This option is available on other phones.