I think they are not supposed to ask you for new forms if they recieved your application on July 31. The letter they send us says this:
"applications received on or after August 1, 2014 must include the following forms:
• Application to Sponsor, Sponsorship Agreement and Undertaking (IMM1344 08-2014 or later);/...."
Since your application was recieved before August 1st you should be fine. The new version was probably not even avilable then. I might be wrong, but I think you will hear from them first when you get your SA approval, which hopefully will be soon as the timeline on the website says they are working on applications recieved July 31st