I've been in a few companies which where we had dedicated account managers on MS side. One was even so big that there were MS engineers sitting with our teams.

I've been in a few companies which where we had dedicated account managers on MS side. One was even so big that there were MS engineers sitting with our teams. Questions of actual substance were rarely answered satisfactorily, sometimes weeks of chasing got nowhere. With this context I would not hold by breath for them to come back with anything useful. Also having seen the kinds of untested garbage they deploy as services I would not be surprised at all at them silently losing data, I would not even be sure for them ever noticing that they have lost data. For anyone using their storage as backups, I recommend having an inventory (with hashes) and comparing that to whats in MS from time to time. At least you know you are not going crazy, even if MS never trusts your proof about their incompetence.