When you are supervising unloading of your vehicle, the tachograph switch should be in the mode:

The term "other work" covers all of a driver's professional activities that do not involve driving a vehicle, such as loading, unloading or their supervision. As supervising unloading is part of professional duties, this time must be recorded on the tachograph under this specific category. Selecting another option, such as rest, would be inconsistent with the work actually being performed.