Finally solved by adding a text field at the login where the user should write the device name. Definitely not an elegant solution but we all know the problems about updating legacy code in a production app, and is the only way to obtain the same device name as before. For your interest, the problem was that the production entitlement was never granted but in the certificates web there was a bug showing it enabled for production. You can check if an entitlement is really granted with the command line app.

Hi, thanks for your help, unfortunately this didn't work, so we are going to spend one "support ticket" ($$$) for trying to solve it. I will reply here when it is fixed.

Thanks! But it appears to be enabled for deployment.