Hi gbotley
There are no separate interview days for route 1/2 and 3.
As you know (having used your blog in part to prep), you apply, have your initial screening, then do your PILAPT and maths day and then come back for the group day if successful.
You don't get offered group interview dates based on your route as you don't actually know which route you are on yet for the most part. You just get offered open dates.
There was a greek man on my group interview day who had already been told they were on route 3 (i think because of some qualifications issue but not sure) but the rest of us had no idea.
After the group interview day, i was told i was successful but it took a month before they told me my route.
I would say that there is no real competitiveness with the routes and the reason i say it is because I would assume that they would prefer all their applicants to go down the MPL route. i.e. if 40 applied and 40 were MPL standard, would they not want to offer all 40 the MPL route? (obviously with possible different start dates) On the candidates side, yes you probably want the MPL but if you haven't got the necessary academic qualifications, you won't be able to do it and so there is nothing to compete for.
I may well be wrong but that is my take on how competitive the routes are.