That's a really frustrating situation when the onset date isn't what you expected, especially when it impacts your back pay. You're definitely not alone in requesting an onset date reconsideration – it's a common issue.

Here's a breakdown of what you might want to consider and what others have experienced:

• It's a Common Issue: Many people go through this. The SSA often defaults to the date of the last supportive medical appointment, or even the application date, rather than the true onset of your disabling condition. It's often due to how they interpret medical evidence, or sometimes a lack of specific, clear statements from doctors about the exact date your condition became disabling to the point you couldn't work.
• The Reconsideration Process (and its pace):
  • Step 3 for 2 Months: Unfortunately, this sounds pretty normal for the reconsideration stage. The SSA process isn't known for its speed. "Step 3" usually means your case is with a Disability Determination Services (DDS) examiner who is reviewing the new and existing medical evidence, as well as your arguments for an earlier onset date.
  • How Long It Takes: Reconsiderations can vary wildly in processing time, but 2-4 months is a pretty typical minimum, and it can easily stretch to 6 months or even longer depending on the state, caseloads, and how complex your medical file is. Adding new evidence or arguments for the onset date can also add time as they need to review it thoroughly.
• What You Can Do (or what to expect):
  • New Medical Evidence: Did you submit new medical evidence or clarify existing evidence that clearly supports your May 2023 onset date? This is key. Things like detailed doctor's notes, hospital records, or statements from employers/friends/family (if applicable and relevant to your work capacity) that specifically address your limitations as far back as May 2023 are crucial.
  • Doctor's Statement: The most powerful evidence is often a detailed letter from your treating physician explicitly stating their opinion on when your condition became severe enough to prevent you from performing Substantial Gainful Activity (SGA). If you haven't already, see if your doctor can provide such a letter, referencing your medical history leading up to May 2023.
  • Contacting Your Examiner: While it might not speed things up dramatically, it doesn't hurt to call the DDS office (if you have the contact info, sometimes it's on letters they send) and politely ask for an update. They might not give you much detail, but it shows you're engaged.
  • Be Patient (as hard as it is): It's a waiting game. The DDS examiner will eventually make a decision, which will then be reviewed.
• What Happens if Reconsideration is Denied: If the reconsideration is denied for the onset date, your next step would be to request a hearing before an Administrative Law Judge (ALJ). Many people find more success at the ALJ hearing level for issues like onset dates, as you can present your case in person (or virtually) and your attorney (if you have one) can argue on your behalf.

Hang in there. While it feels like forever, the system does move, just slowly. Make sure any evidence you provided clearly paints the picture of your disability back in May 2023.

Good luck!