Walekum Assalam
From what I have seen in the last 9 months on this forum, they do the initial review after 10-12 months of the file transfer usually. People who had their file transfer to Islamabad in Nov/Dec 2010 and January 2011 still are waiting for their initial review to be done. So it has crossed 14 months for some people. But we are hoping that CHC-Islamabad will start the initial review on these files in January 2012. From there its a quick process of 3-4 more months if everything is clear and the case is strong and straightforward. Also, husband cases take longer usually due to a second background check.
The first step after the initial review is for them to send a Re-PCC (updated PCC) request and a few forms that were initially filled with the application. The reason they ask to redo some of the forms is to see updates like if the person has changed work/school/completed education etc etc. They ask for Re-PCC to check if there was a criminal record of the applicant since the last PCC was issued. If the case is without rukhsati and not strong (i.e. satisfactory proof of relationship) then they also send either an objection letter asking for rukhsati to be done or for more proof (i.e. proof of visit). It all depends on the immigration officer dealing with the file.
The next step for them to evaluate the updates and ask for remedical to be done (as its expired in 98% cases). Sometimes they issue the PPR along with Re-medical depending on their Visa quota. Otherwise Passport request comes in after they get the medical updates. Now if the PPR comes with the remedical it takes them 45-60 days to return the passport. If it comes by itself after a few days of the remedical then it takes anywhere from 15-45 days to return the passport.