Just my experience... but I went to the same school from P-12 and if anything, that was problematic for me socially. I was a pretty shy, anxious child in primary school and I felt that by year 6, I'd been pigeon-holed. This is who you are and this is your status in the social hierarchy. I always wished I'd gotten a chance to reinvent myself in year 7 like all the other newbies did. They just got to rock up and declare their hand as they saw it then. Nobody had any preconceptions and they tended to be more popular in many cases because they were new and interesting!