Sequence Number Schedule: Does anyone have it?

I've never seen a schedule but with some simple math you can get a general idea.

You will need the total population of the career field, the number of above zone (AZ) promotions, and the number of below zone (BZ) promotions.

1. ALL AZ's will be promoted in September 2015.
2. ALL BZ's will get promoted in August of 2016.
3. Total population - AZ - BZ = PZ.
4. PZ / 10 = Monthly promotions.
5. You can then get a general idea when you will get promoted.

Assume a population of 100 with 3 AZ and 7 BZ. 9 PZ's would be promoted every month beginning OCT 15 through JUL 16
1-3 are promoted in SEP 15 (AZ's)
94-100 are promoted in AUG 16 (BZ's)
4-12 in OCT 15
13-21 in NOV 15
Etc. Etc.

Caveat: Obviously this assumes HRC and G1 are not shifting promotion timelines for this year group.

Or how about major promotions seems like they are holding on to the info until the last minute

The list you received has the sequence numbers already indicated to the left of your name. In your case, you are #64. The first group that HRC deems necessary to promote will receive order PDQ. If history is anything of a guide, you will see the first MILPER message come out sometime in August (IMHO) with the next group of numbers to be promoted the following month, and so forth each month. There is no rhyme or reason to the amount each month, but last year it averaged about 15/mo. From my research, it is based on funding allocation for MilPay, number of slots available to be filled, retires, stuff like that. I suspect you should pop up on the third or forth list based on your number.
As far as your branch giving you the list, I asked my guy and he told me what it was but didnt provide a document. If you tell him you are trying to organize the promotion ceremony and sync calendars with the primary members, they may be more helpful.