To ngc1277,
I made three SRs in Jan., Feb., and April. Almost all of them gave me regular useless responses, like "case is still pending/currently adjudicating with the officer. please wait for 60/90 days". So sometimes SR is not very helpful and don't make too many SR or congressional inquiry. In my experience, if you made too many SRs, they might cause a delay for the processing of your 485 case. All you can do is most likely keep waiting and if possible, you can try to call the Level 2 representative of USCIS NSC to get more information. Hopefully you can get your 485 approval notice very soon.