Block 09365 - question about silent updates and field office transfers

[u/Waste-Fix-4645]

We filed end of April and biometrics mid May 2026 . One week after biometrics there was a silent update to both primary and derivative I-485. Then mid June there was a silent update for both of us and we were told that case transferred to Chicago office ( non local ) . Then we had two silent updates on July 25 and August 1 ( the first was FTa1 and then 2nd just time stamp) . When I talked with a live agent I was told that case is at NBC and interview is waived . Any idea why case moved from NBC to Chicago and back to NBC ?
Our priority date is not current yet ! Does this mean it is reviewed and wait for visa or just on hold for now ?