Boat mode on VTOL confuse me

Hello. boat mode on VTOL confuse me.

from this article, I disable gyro calibration after boot, with INS_GYR_CAL parameter.

as I will fly my VTOL on moving ships in south pacific.

but how can I manually do acc and gyro calibration?

I heard that pre_flight_calibration on VTOL doesn’t support it. from here :