In that case I wouldnt worry about the tacho - its Nina from HSE you need to be concerned about with her load security panicing.
Honestly can’t see them pulling that unless they are a car nut and then they might actually be a bit nicer since its not a horsebox. I guess this is a hobby rather than your fulltime job?
All you need to worry about:
15 hours working time 3x a week or 13 hours normally
9 hours min rest 3x a week or 11 hours normally.
Might be worth taking your MOT cert in the truck as really oddly its not showing MOT for me either. Not sure if its a glitch or this is what comes up on ANPR. Trucks at work just say “data not held”.
Legal bit - Just remember its your licence so dont let the boss push you to drive when you’re not fit. 
Ps: anyone know if WTD applies?