Hi there, for second year PT is summative and OSCE is formative (just show up). If you fail PT3 in summer then there is a resit period in July/August. If you fail your PT resit you may be asked to leave the course or resit depending on a variety of circumstances. I'd say your best bet is to attempt the resit and contact your personal tutor.
I know a few people who have had to resit 1st, 2nd and 3rd year and some had a degree of personal circumstances surrounding their resits. In these scenarios GKT will most likely ask you to resit the year as it is not fair to sit a retake if under external stress.
Hope that helps!