This is under the National Guard thread and trust me, with my nearly 7 years in the Guard (now I am active with nearly 16 years AFS and 2+ years in the Reserves), promotions are different.
When your name comes up as eligible to be promotion for a grade in your state, the opening might be in a unit 100 miles away from your current unit. If you do not take the position/promotion, your name goes to the bottom of the list.
I was combat engineer in the Guard and there was an abundance of positions open, so you can move up to E-6 real fast. Then I switched to 42A and there was an opening in my unit, when I became eligible for E-5. I was lucky.
Melissa, I do not know what state you are in, MOS and the unit that is offering the position (e.g. airborne unit) but I will talk to your state's retention NCO on the best course of action for your situation.
WO1/Rock, this is similar as trying to get a position at the 82nd or 173rd in Italy where being jump qualified is a requirement. And if you are not, going to Airborne school TDY en route to get the assignment as part of the PCS deal.
There are no E-5/E-6 appearing before the board in the Guard. It is all a paper board based on the points you have earned (e.g. PT, awards, correspondence courses, NCOES, etc). That is why you see 50-year old Specialists in the Guard because they cannot get promoted due to lack of slots or they self-deny promotion based on a variety of reasons (slot opening too far from home and/or they love their current unit).