Dear Sheryar khan,
Noor Jattak has explained well to add more. . . .
Quetta City: Main Quetta City or Quetta District.
Quetta Zone: It is comprised of District Pishin, District Killah Abdullah, Some Rural Areas of Quetta and District Chagai/Nushki is also included in it.
If you have Local or Domicile Certificate of Quetta District you can appear in the exam and contest for the reserved seat of Quetta City. Otherwise if you have Local/Domicile of District Pishin, Killah Abdullah & Chagai then you have to contest for the seats of Quetta Zone.
Today I was there in Commission Office & same scene happened. Actually seats of Section Officers have been advertised and according to the allocation policy neither Quetta City nor Merit has reserved seats. So you are not eligible if you belong to Quetta City. You can view the advertisement
here. You are ineligible due to non-availability of seats not because of Quetty City.
Dear you have to wait for some time. I've information that there are chances of many vacancies to be advertised by the Commission. They will extend the date for submission of forms in case they increase the vacancies.
regards,