Hi Everyone, 
Tracking this thread for a while. Here are my experience with picture and timelines if it helps :
10/15- Landed at Pearson, Toronto from USA
10/18- Linked PR app to my CIC page. Myself ( Primary applicant), spouse and two children.
11/20- Called IRCC to update my delivery address.
11/20- My additional doc status changed to : 
"The Additional documents you have provided has been uploaded." 
           Status for my spouse and children remained: 
"No additional document required."
11/28: My Spouse additional doc status goes to
 "The additional document you provided are being reviewed"
11/29
: Both children status changed to 
"The additional document you provided are being reviewed"
12/01: Spouse gets email from IRCC for 
New Photo Request. She got the email on her email ID. 
12/04: Status for myself and two children is "
Approved." 
           My addition doc request is still :
"The Additional documents you have provided has been uploaded."
          Children's is still: 
"The additional document you provided are being reviewed"
About picture:
No studio in USA could give me right measurement so I had clicked myself using my DSLR and edit using 
https://www.idphoto4you.com/ and then printed at Target. I was not very careful while editing and deviated from actual measurement while editing. ( Didn't know then that IRCC is so particular)
Mine was exact per the requirement. spouse picture were slightly off and children were much off. So I am assuming IRCC relaxes the requirement for children, but sticks to exact requirement in case of adults.