RS2 was calibrated, but not RS2+ or RS3. The results have been propagated (cut and pasted) across the other two in the atx file.
And GA’s & IGS interest is the accuracy & precision of static observations.
So for both reasons expected that IMU would not be calibrated.
Discussion here:
Emlid Reach RS2+ / RS3 Antenna Options in Software - Reach RS3 / RTK / PPK configuration - Emlid Community Forum