Andrejs:
tachograph:
You can have 2 extended driving days (10 hour drives) in a fixed week Monday to Sunday.
You can have 3 reduced daily rest periods between weekly rest periods.If you work Saturday to Tuesday you could have extended driving days on all 4 days because you will only have 2 in each week.
If driver start drive Sunday and finish Monday morning and was done 9+ driving time.It is counted form last week or new week.
The regulations say that “the daily driving time may be extended to at most 10 hours not more than twice during the week” so I would say that if the 9 hours driving time is extended after Sunday midnight it counts as an extended driving day for week 2, otherwise it counts for week 1.
Though I should say that I’ve never seen any confirmation of this by the DVSA.