Originally Posted by DaveS

You have asked a very good question there. Logically there should be a lower age limit for the day 5 TTR, but there really is nothing in the guidance. The legislation just references the guidance, so no help there. My instinct would be to not book it. If things go wrong later, you should be able to opt into it by filling out another PLF or editing the existing one. Not having it on the PLF will not stop you from flying back. Unfortunately these rules are full of holes like this.