I agree with you on both items.

I got the 30-day notice on my 485 case long time ago, but my priority date will become current in June, so it is not approved yet.

I went to the infopass a few months ago and learned that my NC is clear. I totally agree that, if you NC is not cleared by FBI, USCIS will not give you the 30-day notice.

I think you should get your approval notice soon if your fingerprints record has been settled.