According to
http://warsaw-visaguide.hypermart.net/provision.htm, you are correct. Applications get divided by region the beneficiary is from.
QUOTE
THE PROCESS AT INS
Mail Room: Your Petition will arrive at the INS Service Center's mail room with hundreds of other Petitions.
Intake: Your Petition will be taken to an Intake Clerk from the Mail Room. This Clerk will look it over for all of the proper forms. They will not examine any paperwork, but simply take the form checklist (that they have memorized by now). For example, the checklist will say "(1) Form I-129F, yes here; (2) G-325A's, yes here, (1) Birth Certificate, yes here, etc." Your Petition could sit on the Intake Clerk's desk for days, especially if the INS Service Center is busy.
Processing: Your Petition will be sent on to the Processor from the Intake Clerk. This person assigns your case to a specific Examiner.
Examination: Your Petition will be sent on to the Examiner from the Processor. This is the actual person that inspects your Petition to verify that your relationship is valid, that you are an American Citizen and so on.
Central Processing: Once approved, your Petition moves to Central Processing, where a Divisional Director separates your Petition by region, Asian, Central America, Eastern Europe, Southeast Asia, etc. This task is only for categorizing your Petition.
Outtake: After being classified by region, your Petition is sent to an Outtake Clerk. The Outtake Clerk assigns your Petition an "A number" depending on your region.
Distribution: After being assigned a reference number, the "A number", a Distribution Clerk will carry out any special acts, such as cabling the Embassy. The acts are a result of notes made by the Examiner, not you by you.
Information: If you call INS, you will speak to an Information Officer. This is a glorified term for "INS Secretary." The only access they have is the INS Service Center's computer network, which will not tell you anything more about your Petition's status than you hear on the INS telephone voice message. They do not interface with Examiners, who are much too busy examining than to cater to specific requests.
EXPLANATIONS
Non-sequential examinations: Approval is happening to other K-1 applicants who submitted their Petition after I did (according to the I-797 notice date). At the INS Service Center, various Petitions are randomly pulled from the files to train new Examiners. Most likely, an experienced Examiner grabbed a Petition out of the stack to train a new recruit right there at his/her desk. They then subsequently approved the Petition (lucky Petitioner!). The Petition the Examiner grabbed may have been anywhere and hence explaining why it was "out of order" or why the approval date is earlier than other Petitions with earlier I-797 notice dates. This is happening everyday, Examiners are training new recruits everyday. If your Petition was approved in a very quick timeframe, say within 10 days, it was most likely pulled for training purposes.
Request for more information: There are no rules here, just based off of the Examiner's judgement. If the Examiner requests additional information, it will delay your Petition from about 1 week to as long as 1 month, typically. Your Petition will most likely be sent to the "back of the line." Possible reasons for a request for more information include:
Your fiance(e)'s last name matches another last name of a Beneficiary from a previously fraudulent marriage. Supposedly, INS holds a list containing the names of previously fraudulent K-1 marriages.
You or your fiance(e) did not sign the I-129F or G-325A form
Examination is 15 minutes: The actual examination process typically takes 15 minutes, that's it. On to another Petition.
Priority given to most paperwork: If an influx of non-I-129F paperwork arrives at the INS Service Center, your K-1 Petition could be sitting for a very long time, until the backlog of other paperwork is examined.
K-1 decision legally set at 30 days: No, nothing legally binds the INS Service Center to process your K-1 case within 30-days. Unfortunately, the goal of within 30 day processing is stated in most of the INS Service Center guides, but may not necessarily be followed.
G-325A carbon copies: The duplicate G-325A carbon copies are not used anymore, the INS Service Center actually will throw these away. Your whole Petition will eventually be filed electronically, once the Outtake Clerk assigns it an "A number." Still, you should definitely submit your Petition with the carbon copies, but no need to worry if not every carbon copy is legible.
NSC: The Nebraska Service Center typically processes as much paperwork than all three other INS Service Centers combined. This may help to explain longer waiting times.
File cabinets: Petition paperwork is held in file cabinets before the Intake Clerk pulls it for examination.