A combination of preadjudicated cases and new EB3-WW cases doesn't help.
I'm not sure the chances are diminished. If visas run out mid way through September, it was always unlikely it would have been approved within 45 days of Receipt anyway. Even with an early walk-in, it might take 30 days to get the biometrics done.
If your date remains current in October, you may have a chance of an approval if there is no RFE, but even 90 days would have been considered quick until fairly recently.
Either way, the EAD processing time shouldn't be impacted.