Generally Three Reasons delay response from VO.
1) Adding dependent
2) Late PCC submission which makes delay in background check.
3) Not updating the schedule A from age 18.
I am almost 100% sure that all who are waiting for MR & PPR now, have/had at least one of the above pending.
Adding dependents:
Completing documentation and medical always take a significant time (apx 2-4 months) by VO on the top of regular application process time. If it's newborn, things are bit easy but for spouse it's longer due to background check. Again adding dependent like spouse is always better at this stage because in Canada it's difficult as different sets of rules apply with around 1-2 years of process time.
Late submission of PCC:
We are supposed to submit along with the main application last year. So it happens like this, PCC goes for background check, it's a simultaneous process with application processing, so the VO processed everything but as PCC was not there with application, that part of background check could not be initiated. So he asked for PCC later with MR/RPRF, which we think is ONTIME, practically LATE by at least 6 months. And for multiple PCC with frequent travel history, this background check takes longer time (1-6months).
Schedule A:
Also once schedule A is submitted again on VO request, which was submitted before in main application, means it was not filled up properly, so on our 2nd time submission, it requires further work by VO. Remember VO could not complete the job at one shot, so he kept a future date to review our file again, when he will touch the file and check if we have fulfilled his requirements that time. Otherwise he will again put another date.
Hope I could remove a bit anxiety from our MR/PPR party.
Best of luck all.