VIA flips car line number order around on occasion for unknown reasons. For the last several years, the 10 car line has been the forward most sleeper, with car line numbers ascending from there back. Before that the 10 was the rear most Sleeper Plus, with car line numbers ascending going forward.
It looks like they've switched the car line consist order again. I am in VIA 2 at this very moment (sitting in Edmonton), and in this consist the rearmost sleeper is the 10, with 11 and 12 forward of it.
The 11 car will be either the second forward most sleeper or the second rearmost sleeper. Since VIA switches back and forth, it is hard to say, but since the switch back to 10 rearmost then ascending going forward is a recent change (since April), I think chances are slightly better it might stay that way for at leasta little while.
May will have a long consist. There may be two diners and two Sleeper Plus Skylines on it.
Note if the car lines are numbered ascending from the front rearward, you will be a very long way from the Park, which have restricted hours for Sleeper Plus passengers in May.