Sitting next to a provisional license holder (help please)

I have held my car license over 3 years but only held my class 1 a year. I have a mate who has passed his class two and we would like to know if i can sit next to him whilst he drives a class 1 on L plates. Obviously with the correct insurances.

I know to sit next to a learner you have to have held your license for 3 years minimum but what i wasnt sure was is that a minimum of 3 years of having held any license or if it had to be the licence type you want to supervise.

3 years in the same category.

An exception to the 3 year rule is if someone has held a full Cat D PCV licence for at least 3 years then passes Cat C, the waiting time to accompany a learner is reduced to 1 year