Hi vermas,
Actually there are some exceptions regarding the AOR from Buffalo for unknown reasons. To be honest with you, it is not related to the time of year when you have sent your application.
I remember when i sent my full application to Buffalo on Sep 2009, i got my AOR within 28 days exactly by email, meanwhile, some members here in this forum who sent their applications around the same time, even before i did by 1 and 2 weeks did not get their AORs in the normal timeframe for unknown reasons, which is supposed to be one month or less.
Some others did not get it at all, but they have been able to see the change on their e-case from "CIO eligibility review complete" to "Received by the visa office" using the CIO file number.
The most important thing here if someone has not got his AOR in the normal time frame at least is to see the change on the e-case to read "Received by the visa office", because in this case, it means that they accepted his file regarding the (completeness), and created a file for him on their system even if they have not sent him the AOR with the new file number "in purpose or by mistake".
In respect to the 5 months which they state it might take them to send the AOR, it does not really take that much.
The things that might not be a good indicator in this case are:
Not seeing the change on the e-case status after sending the full application to the visa office (if there is no AOR sent by them for long time, let us say 3 or 4 months), the reason is because this case might mean that the application is in its way back to the applicant to be re sent after fixing some mistakes on it.
In your situation, you can send them an email enquiry, but i am sure that they are going to send you the same copy and paste message wich says:
"Please allow 5 months from the date of receipt of your application to this visa office to receive our AOR or get your application back".
If you would like to send them the email, go for it, but i am sure that their answer will not be satisfactory for you at this time.