XM1110 firmware has changed its baudrate

After having ordered a new batch of your XM1110 GPS modules, we came to the unpleasant conclusion (after some troubleshooting) that you have changed the firmware of this module. Notably the baudrate has been increased from 9600 to 115200 according to the new data sheet, a speed our design cannot handle (there will be interrupt conflicts). However, the modules we have only respond to 38400 baud! Even worse, the command to change the baudrate has apparently been disabled. As a direct result, this upgrade has rendered our whole series of hardware products useless! Our clients will not be happy.

Is there a cure for this problem? Maybe a possibility to roll back the firmware on our batch of modules?