what is the Officer Familiarisation event?

Hello, I am not sure if you are referring to an officer familiarisation event for a specific cap badge, or just in general. But essentially it is a chance for you to see what your life might look like once you commission. It has been a few years since I went on mine, but I still attend as an RAMC officer to answer questions from potential cadets. From what I remember, for doctors at least, we had a series of lectures on what the army is now, and how it is likely to develop, and we had talks from officers that have gone down various different career paths. There is usually a chance to have an informal discussion with junior officers, this is helpful when it comes to asking questions you don't feel comfortable asking at interview (I often get asked things about how much annual leave we get, how much we get paid, how easy it is to see friends at the weekend and how hard it is to maintain a relationship while moving all the time etc..) It was also a chance to meet all the other potential cadets that you may end up going to RMAS with. I found it a really useful, and we often get positive feedback from the potential cadets that attend our events, so I would recommend going!