Hi!
Yesterday just before sending our compIete application i realized that the form Generic application for Canada 008 had been updated. My husband called to IRCC and was told that we could still send the old form because the change was minimal and very recent but that we should do it asap and we did it.
At that moment the checklist was not updated. I think that update is from today. For that reason we sent our package to Missisauga.
If you want you can call early tomorrow to confirm if you can still use the old forms.
I guess they will give a grace period like when they updated in February, but it's better to be safe!