Is this shift pattern legal: First shift since Jan 22nd was Monday 12th Feb.
Work Monday 12th Feb
Off Tuesday 13th Feb
Work Wednesday 14th Feb until Monday 19th Feb
All 10hrs shifts 6hrs driving.
Off Tuesday 20th Feb
Work Wednesday 21st Feb
Off Thursday 22nd Feb
Work Friday 23rd Feb until Sunday 25th Feb
Off Monday 26th &2 7th Feb
I know the Wednesday-Monday is legal, but do I need to take Wednesday 21st off as well as Tuesday 20th because I already reduced my weekly rest the previous week.
i would say yes but might depend if you work the weekends
Technically as you have not worked since January 22nd the 45 hours rest up-to when you start work on Monday 12th February can count as a regular weekly rest period for the week beginning on Monday 12th February, so legally you only need a reduced weekly rest period in the week starting 19th February.
Assuming that it’s more than 24 hours rest, the day off on Thursday 22 February can be used as compensation for Tuesdays reduced weekly rest period.
The reduced rest from Monday 20th at 18 00 finish until Wednesday 21st would be 38hrs approx then another 38hrs approx rest until Friday 23rd Feb
You mean Monday 19th not Monday 20th 
By the end of the week ending 25th February you will have paid back the compensation and had another reduced weekly rest period (not that it’s needed).
Ok, thanks for the information
