So, return envelop is not empty. Return envelope has 2 Passports ( self and spouse) with visa , 4 COPRs ( 2 per person) and 1 cover letter stating next steps, rules etc etc.
Noticed that visa issue date is incorrect. It's 9th Nov 2017 instead of 9th Dec 2017 ( but then 9th Dec was Saturday !!!.

) Most probably passports are returned in order of visa date ( 9th Nov in my case) and that's why my return tracker got activated within hours of application approval.
EDIT: I am being told that visa issue date is the date when Visa Officer makes decision on your file. SO 9th Nov looks right now.
Here is my final timeline:
Stream: QSW
PPR Date: 8th Nov 2017
Passport Sent Date: 9th Nov 2017 ( By Fedex from East Coast, USA)
Passport Delivered Date: 10th Nov 2017
CPC Approved: 11th Dec 2017 ( in MyCIC, no email, visa issue date is incorrect - 9th Nov 2017 instead of 9th Dec 2017)
Return Tracker Activated Date: 11th Dec 2017
Email of update in MyCIC: 12th Dec 2017 ( no real update observed, I guess update emails are sent 1 day after approval)
Passport Received: 12th Dec.
Good luck everyone !!!