More than one champion at mastery 5

So what happens when we have more champions than one at mastery 5? By this i mean in terms of our profiles, how are they positioned?

Are they set up as #1 being your most recently played, and #2 and #3 are the next two (Play a game as all three, the most recent one #1, the first one you played is #3)?

Are they set up so that the very first one you get to mastery 5 is permanently #1, the second #2, and the third #3, while all of the others don't show up? Or vice versa (the very last three champions you master are the top 3 shown on your profile)?

Will we have control over which ones are shown as our top three?

Personally I would like to have the ability to set up our top 3. I would love to have my profile show as #1, as #2, and as #3, but I don't know if that will be possible due to a lack of information.

If anyone has gotten to more than one champion at rank 5, I would love answers!