I suspect the former American resident receiving the amounts might argue that not being in the same position that he or she was in back in 1995 is unfair to them, and it's for that reason that this change is very targeted. It's only available to those who were in that position in 1995 and have been continuously resident in Canada and in receipt of these amounts since 1995.
On April 22nd, 2010. See this statement in context.