Riot said that when you are gaining mastery points, you get graded in different things. One of the website that explains mastery level said
"For Example, Mid Annie and support Annie will be graded differently."
And of course it make sense. BUT HOW CAN THEY KNOW IF YOU ARE PLAYING SUPPORT OF NOT?
The game doesn't actually look at the role at champ select, and instead figures out based on stuff like map location and how you play. It is smart enough to recognize lane swaps and stuff without getting confused, although it is occasionally possible for it to get thrown off if for example you're 'support' but you take cs and spend a lot of time roaming, then it's possible you might end up graded as a jungler instead. If you play conventional roles in a conventional manner though, you'll probably get graded appropriately.
There was a podcast around the time of hextechs release that talked about this sort of thing that might be worth digging out if you really want more info, but what I said is basically the gist of it.
(A side effect of the above is that even if you swap roles at champ select you'll still be graded appropriately, and similarly you can't duo with someone in bot lane and play the opposite role you were assigned to get 'easy' good grades, since you'd still be graded based on the role you were actually playing.)
Because you picked Support Role, you're labeled as Support, and you will get your champ graded as Support. It's pretty clear cut.
Ok, so if it doesn't rate based on your role selection, then why wouldn't everyone be graded as junglers once late game occurs and creep is up for grabs and everyone roams?
