When CIC receive your application, they will compare the date you SIGNED your application (and the residency calculator) to the date on the day they actually receive the physical file of your application from the post office service or any courrier service you use. If the difference is 90 days is more, your application will be considered "stale-dated" and will be returned to you. See below link, Question 10.ARD1979 said:Thank you for the comment.
But 90 days from the date of my application signature or 90 days from the letter that they put on my returning application?
What makes you so certain about this period of 90 days?
Cheers
http://www.cic.gc.ca/english/information/applications/guides/CIT0002ETOC.asp.
On a side note, you may need to know that nobody on this forum is 100% sure of anything... we give advise on the best of our knowledge and experience and it's up to you to make sense of all and decide on the proper course of action for you.
Good luck