Originally Posted by
Chesty Morgan
I'm not sure how reading back the TL improves anything. When I'm cleared to an altitude I set the QNH straight away. That's the SOP at my current airline and the previous two. Doesn't matter what the TL is.
Exactly, it's only in the unlikely event that ATC don't want you to change to QNH until you have passed the TL that you need to know it, otherwise as Chesty says, if you're at a flight level and cleared to an altitude, you set QNH and descend.