I don't think that anyone can reasonably predict how long it will take for the National Benefits Center, among other reviewers, to resolve the concern. It is unclear whether the USCIS thinks that you are somehow disqualified from adjustment. More information is needed.
At times, oversights are made and additional evidence is required. The USCIS has the right to review and may rescind an application at its discretion. Of course, an applicant may appeal a decision, where the applicant believes that mistakes were made.
If the mistake is on the I-140, then only the petitioning employer can appeal. If a mistake is on the I-485, then this can prove more complicated.
I strongly recommend an appointment with an experienced immigration attorney. You should have an attorney present at the USCIS interview if one is scheduled. If there is a request for additional evidence, then this should be handled by an experienced immigration attorney, as well. Good luck. At times the issues are not as complicated, but USCIS delays are legendary once a matter is transferred for further review.
The above is general information and does not create an attorney client relationship.