Best/Easiest way to work out overtime

I am a fairly new driver so you would assume that all the drive time information that I learned for my test would still be fresh in my mind, however I worry about going over my working hours.

I work on a 5 on, 3 off rota and for the past few months I worked alongside another driver who was on the same rota as me and he was always good at telling me if I was able to work overtime on which weeks. He has since left the company so I cannot ask him for advice.

My company usually asks if I can work an overtime shift on the following week but I don’t know whether I can do it or not depending on what day I start my first shift in the week.

I was caught out over Chistmas and New Year when I done 90 hours over the 2 weeks and the company sent another driver to pick me up so I didn’t go over the limit and since then I have not done any overtime on offer just to be sure that doesn’t happen again.

The other driver used to tell me “if you are off on a Sunday, you cant work overtime”, however I have spoken to other drivers and one said “If you start your week on a Monday or Tuesday, then you can do an extra day” and another driver told me “if you start on a Tuesday you cant do an extra that week”.

Should it be ok if I work it out to be only working 5 shifts in a week?

I’ve also heard something about not being able to work overtime for a couple of weeks in a row and then you can work overtime for the next couple of weeks consistently after that until the cycle comes around again when you cannot do it.

All of the statements above might mean the same, but which one should I be using as gospel? Also, there is some confusion on what happens if I do an extra shift as the first day of my week or do the extra day at the end of my week.

Can anyone shine some light on this? Maybe have a specific algorithm which would ensure that I do not break the law.

I should also say that I do trunking, usually 8 and a half hours of driving a day.

Any help much appreciated.