"Pax is to expect only a $200 refund??? That doesn't sound right."
Full Y is never much less than a C/J class fare, so it sounds about right. Actually, I'll let the system decide.
Full C/J class YYZ-LGA return on AC is showing at the moment for $1520.00 base fare, but found a discount C/J for $1334.00. The full Y class fare is also coincidentally $1334.00 as well, so the figures don't add up somewhere. Either AC is being generous and refunding the difference between full Y and full C against his what looks like discounted C, or they've not realised he was on what looks like a discounted C.
(Got the figures from using 1100 departure ex YYZ 23 Jul with a 1110 return on 25 Jul ex LGA).
Bumping of J class pax back to Y has happened over the years but rarely because of deliberate overbookings. More normally an equipment change or seat malfunction etc. If they're gunna do it, then you'd hope they are studying the numbers a little more carefully. Don't know how Mapleflot operates, but I know the USA carriers for the most part hide behind the fine print in the conditions of carriage for all manner of things. Think they'd cover themselves under the only obligation is to carry from A to B clause.