Jagman might have a different view but unless your firm implicitly request you use period of availability (know often as POA) ignore it.Cheers. What does period of availability mean? Surely, if your not driving, or on a break, it’s other work? What the point in that symbol?
Also for example, could you do other work for say 45 minutes, then drive for 4.5 hours straight through without a break?
If the time can be used as POA it can be used as a break. So to avoid any hassle (tacho can reset driving time inadvertently using POA) I just use break and have done since 2007 approx and not once been pulled up on it.