Development key failure after date change

Hi.

After modifying the date on the Pro+ and following a reboot caused by a power failure on the same day, our development key is no longer recognised by the system.

The dongle has been checked on two other systems and is recognised fine.

Other license keys have been checked on the system and are picked up.

Checked the key using Watchit and DONGLEDRIVER and the key is recognised.

Checked using SYSTEMIDKEY and it is not updated.

The date has been changed back to the 'wrong' date and the system has been rebooted but the development key is still not recognised.

Any advice is gratefully received, or should Emerson be contacted?