Just for info . HO will process applications on date order only.
There might be some discrepancy . Even though they stamp the applications on its arrival which at times is hard task .... They might consider the INPUT DATE ( Date on your acknowledgement ) as the date application received and hence there will be a slight discrepancy for any applications made in the last few days of month .( Please don't assume things ) .
Check you acknowledgement date and that would be the reason some applications are considered as September even though they posted in August .. as I explained sometimes your applications sits with a lazy officer while other applications are dealt with .
Explain more clearly dealing with applications.
Assume Aug has 75 applications
25 applications ----1st aug till 10 Aug will go to one office ...... he may be fast and process everything
25 applications -----11th Aug till 20 Aug will to another ---------- he may take more time to process
25 applications-----21th Aug till 30 aug will go to third ----------- He does it at lightening speed
In this scenario there is a possibility that 11 aug - 20th applicants wait more than the others
and thats the reason we get the decisions not in a date Order I hope this explains .......