Calibrator now includes the ability to upgrade controller firmware in one step right inside Calibrator, and that step also includes converting the existing MOD file you have on the ECU to match the new firmware.
Upgrading the firmware should of course still be done cautiously to older installations/versions of ECU’s as strategies change and will most likely require tuning, so be prepared for that.
It is advised that every new ECU is upgraded to latest version before any tuning work is started.
Also please take note:
An internet connection is required to discover new releases and download them, but once you attempt to upgrade to a new firmware version, the software keeps a local copy of it cached so that when you get to the car, it is capable of installing firmware without requiring an internet connection.
-B.G