This is not a mistake, this is for real, so believe it!
The 10 months is NOT an average. It is how long it takes your VO to process 80% of applications.
When you look at the timelines a bit more in depth you will understand a bit more about this. Go to
this CIC website page and click continue. It will ask you to open or save a spreadsheet, this spreadsheet has more information.
On the spreadsheet, you are looking at all visa offices' average numbers. Now change the "all points of service" dropdown menu at the top, to Buenos Aires. The spreadsheet will update now and give you numbers for Buenos Aires only. Somewhere on the bottom right you will find percentages for spousal family class.
As you can see, it has in the last 12 vmonths:
-Taken your VO 4 months to process 20% of spousal applications
-Taken your VO 5 months to process 30% of spousal applications
-Taken your VO 6 months to process 50% of spousal applications
-Taken your VO 8 months to process 70% of spousal applications
-Taken your VO 10 months to process 80% of spousal applications
So, from this you can draw the conclusion that either you were amongst the 20% who were processed in 4 months or less, or your VO asks for your passport very early on in the process.
I hope this is a sign that your processing is complete, in which case I want to just say congratulations.
Edited: Jumped to conclusions, sorry