Make sure you keep both your NPPL and the LAPL.
Unlike all other licences, the LAPL has a rolling validity.
So the other day one of the chaps here - who did an hour with an instructor more than 24 months ago - was able to use his NPPL SSEA to fly to another airfield to go for an hour with an instructor. He could then fly home on his LAPL!
He couldn't use the LAPL on the way there because the first-mentioned instructional hour was more than 24 months before the the date of the flight.