GC issue is a permanent visa controlled mainly by constant number for each category which is equal for all countries, India like small island both have the same number. If the applications are huge, this will make the waiting line for those countries with storm of applicants very long and the first come the first served to the maximum number allowed for that category per year.
Processing time is something different, which is the time required to process the application which is usually few months (revision of application, security check up, ......etc).
If the priority date is current, which is the case for almost all countries but India and China (as we said because of humongous number of applicants that exceed the maximum number, especially for EB3 which almost every one could fit in) the GC will be approved around that processing time.
For you, because your PD is not current, do not bother by the processing times which is something that indicate that the USCIS processed the applications applied before that date. If PD is current, well and good, this is = approval, if no PD is current, this means that the already processed application will stay dormant till the priority date is current.
The Department of State is the place who track those numbers and make visa numbers current accordingly and the USCIS is the place which approve those applications after then.
Sorry for the redundancy.