This morning, at 8 AM I received a message In my Gmail inbox. About 5 PM I started writing a reply to the message on my smartphone. I wrote about six sentences and when I was about to finish the e-mail and checked back to the original message. And it had disappeared.
The only thing left from it is the part saying: reply to the message from ... sent ... .
The draft of the reply is still in my inbox and marked important. So I thought there should be enough reference for recovery and contacted Google about it and I have already received a reply: there's nothing they can do about it.
So please, be aware Google does not guarantee 100% reliability in their e-mail service. You may get a very very important e-mail and if you have no other copy it may be completely gone - forever. If you need that get another provider. Back up your email you receive there regularly.
And let me quote:
"Because there's unfortunately no more we can do to try to recover these messages, we won't be able to respond to future inquiries."
Maybe they removed the beta label to early...
PS: with two step authentication I think it's not very likely someone would break into my account to delete a private message of a student...