Lots of EASA questions are answered on the other pages of this website, but the questions that don't fit into those pages are answered here. Use the drop-down tab for military questions.
If you have a question that's not answered then please use the contact page and i'll try to find the answer for you and then post it on here for future users. I aim to find the answer within 24 hours using a mix of civilian and military instructors.
What is differences training?
This is covered on the "Extra Ratings" tab and it breakdowns what the CAA consider to be differences in aircraft handling or perfermance. The differences don't go on your licence, you just need training (flight with instructor) logged in your logbook. Probably worth getting the instructor to sign next to the entry as a record of the training.
Who can claim P1?
The simple answer is only the person flying. Normally one person will fly as PIC P1. You could agree to split the time whilst flying with another PPL pilot, but you must be clear who is incharge at any given point, just incase you have an emergency or an airmanship decision needs to be made. For example for a 60 minute sortie, one person could log 20 minutes P1 and the other pilot could log 40 minutes as P1. The only time when 2 people can log P1 is when flying a test with an instructor/examiner.
What can I claim as a club check pilot?
If the check is purely to satisfy a club rule then the answer is nothing. Providing the new member has a current licence and has flown 3 take-offs and landings within 90 days then you are a passenger. You might want to brief a change in command (PIC/P1) if you feel that a safety issue is arising, for example, change of PIC will occur on the call "I have control". If you're an FI/CRI then you can only claim instructional time and P1 if you are performing instructional duties and rental checks don't count. If it was differences training for the member or their bienniel flight then you can claim the hours.
Whats the difference between a Revalidation and a renewal ?
A Renewal check/flight/test is required if the licence or rating has expired. A Revalidation check/test/flight is required if the licence is still current and you have met the hours requirements to keep it current.