I do multi drop work which I normally finish my round by 1pm. Then normally park up some where and wait for collections. Which can be up to 2hrs waiting around.I’ve always left the tacho on other work. But some people have said to put it on poa as will bring down my hours on Wtd.
Thoughts please
I would put it on break.
break.no brainer.end of.
Break. If you’re sat waiting but don’t know for how long you can’t use POA.
Break
As long as you get paid for breaks use break, POA will wrongly reset your driving time whereas a break of 45 minutes or more will correctly reset your driving time.
Neither break nor POA count towards working time.
Seriously 
Have you read and understood the tachograph rules and regs…
Don’t do what others do just do what you want as long as it’s legal…