Should promotion from PFC to SPC be automatic?

Acording to AR 600-8-19 (Something you need to get a copy of and learn so you can continue to make yourself ready for promotion)
(2) Promotion to PFC is 12 months TIS and 4 months TIG.
(3) Promotion to SPC is 24 months TIS and 6 months TIG.
(4) Soldiers must meet eligibility criteria in paragraph 1–10.
(5) Any Soldier previously reduced (for misconduct, inefficiency, or cause) must be fully qualified (without a waiver) for promotion to the next higher rank.
d. If a CDR elects not to recommend a Soldier for promotion on the automatic promotion date, the CDR must annotate “NO” on the AAA–117 (RA) or GRA–PO1 (Advancement Eligibility Status Roster) (USAR), then the CDR (or BN HR) must prepare a DA Form 4187 denying the promotion. A DA Form 268 will be submitted no later than the 20th day of the month preceding the month of automatic promotion. The first-line leader must counsel the Soldier, using DA Form 4856 (Developmental Counseling Form). The DA Form 4187 and the DA Form 4856 must be attached to the enlisted advancement report before it is forwarded to the BN S1 HR specialist. The BN S1 HR specialist must submit a Flag transaction in the personnel system to block the promotion as described below.

Yes, it is "automatic", yet your chain ultimately has to hack off on it. There must be something that is looming in the background that precludes you from the list. And, truthfully, it may be a straightforward as you rubbed someone the wrong way and they do not think you are ready.

Here is where you have to start thinking like an NCO. You are quite right, nagging or whining will definitely fly in the face of what you hope to achieve in advancement. I would advise that you present it constructively. You have the right to now why you are not moving up. ((If your supervisors are tippy-toeing away from telling you, then that is an indicator of their piss-poor leadership.)) Ask your Chain of Command what is stopping it as you would like to improve on that facet of your eligibility.

You simply cannot unf*ck what you don't know is f*ct.

And even if it continues to delay, continue to do good work. It will all come to fruition.

Keep us posted to your progress.

I actually do this stuff for my company. Some people have already said it but if you have been in as long as you say and have as much time in grade you should be a SPC by now. If your command is not promoting you on purpose there should be a paper trail backing up why. I realise this is YOUR rank and this might be a sore topic for you but you have to remember to approch this professionally. Continue to bring it up to your 1st line supervisor. What does your LES say? If you are not flagged or under any type of ucmj there should be no reason you didnt get picked up at 24 months. let me know maybe i can help. Also if your chain of command continues to ignore the problem there is always the IG office or ICE.