Obviously your tachometer is yours and nobody but you can input data,but what about run sheets,if your sheet has spaces to record break/ poa and you record none for the day,how do you stand if a manager instructs the t.o bod to write in x amount of poa on your sheet so the managers ,manager thinks the drivers are putting in poa 
.when there not
Obviously your WTD hours are off of your tachometer but this still sounds a dubious practise to me,I guess there’d be no come back on driver having this done to his run sheet
N.b this is obviously a hiperthetical scenario 
dozy:
Obviously your tachometer is yours and nobody but you can input data,but what about run sheets,if your sheet has spaces to record break/ poa and you record none for the day,how do you stand if a manager instructs the t.o bod to write in x amount of poa on your sheet so the managers ,manager thinks the drivers are putting in poa
Obviously your WTD hours are off of your tachometer but this still sounds a dubious practise to me,I guess there’d be no come back on driver having this done to his run sheet
N.b this is obviously a hiperthetical scenario
If i understand you correctly, then no one should be filling your hours for you , at least certainley not off their own bat in a guess. There’s a few things to make this easier to keep things accurate. After filling in the sheet as required, fill in any empty boxes so they can’t be filled in. i.e if the box requires POA and you’ve had none put in a big “X”. Also employers have to provise to an employee when he requests a copy of his working hours to date, ask for yours. Also point out your concerns that they are accurate as you have seen first hand evidence of them being manually adjusted. At the bottom of the form, fill in manually and seperate from the coloums on the form…2 hours work, 6 hours drive 8 hours total work as per tachograph record and sign it.
If and only if vosa or any legal body want to check tacho and work records there would be a discrepancy and in theory a record of hours are being falsely recored. …
The tacho is the official record so if thats ok then so are you
If internal company paperwork is different to tacho then that is no great problem unless it affects your terms of employment
Thats my view on this and as I said in your other thread - who really gives a hoot about the RTD?