Shift Spanning Start Of Fixed Week

Thanks

Trying to get my head around this scenario…

Week 1 - Holiday

Week 2/3 - Working Sat, Sun, Mon, Tues and wanting to extend driving hours to 10 hours each day… legally okay to do so with day shifts (2 extended drives each side of the start and end of seperate fixed weeks) but can it be done if working all four shifts on nights?

Can’t decide whether it would be illegal to extend to 10 hours driving for the four days in question if driving before and after midnight on Sunday as the Sunday driving hours will be split into two seperate fixed weeks.