It is ok brother.... I am surprised to know from you that one of May application will review on Jan'16...
For my simple understanding if July applicant didn't received their additional documents then sign is good that all applicants submitted their documents as per CIC/VO requirement.
Also you can see from database that some of July applicant has received MR and also second line update. And also you could see one of Aug applicant has received rejection... that indicated that VO already reviewed their documents and satisfied/unsatisfied on applications submission documents.. On that basis VO is responding their processing though.
In the last, that all of my information based on my own analysis and assumption. There is no any evidence that I can provide you. May be someone's info can match and other's couldn't however some analysis could relief some tension...