Regarding changes to the new budget (if anyone is still wondering), I had the chance during a conference to ask an NSERC program officer about whether the new award values would be reflected in upcoming years for current award holders, they said they don't know yet...
Does NSERC normally reply back confirming that they've received your offer acceptance via email? I requested for my award to start Sep 1st, but haven't heard back from them/only got an automated reply.