P: LrC 15.1 macOS 15.7.3 Getting ready to Import problem

I am using a MacBook Pro M3 Pro omputer with 16 GB of memory as I have been for a couple of years. I use the internal SD card reader on the computer which I have tested and it gets close to the stated read speed of the card. The computer has OSX 15.7.3. My Lightroom Classic is version 15.1. My SD cards are ProGrade 256GB, 250MB/s cards. I shoot compressed RAW files on a Canon R6 MKII. I think this prroblem started with the upgrade to LR 15.

As an example, a couple of days ago I came back from shooting 3 basketball games with a little over 6,000 frames on the card, about 105 GB of data. I stick the card into the card reader and the Lightroom Classic import window comes up. I have found that I need to wait many minutes, maybe areound 10 for 6,000 files, for LR to read all the files on the card before I actually click import. If I do that everything works fine.

If I don't wait the 10 minutes, and actually verify that LR has seen all the files, they won't all import.

This also happens with many less photos on the card. I imported a shoot that had about 575 files but forgot to wait for LR to see them all, and ended up with about half the files in the import.

Is this normal? As I said I don't remember needing to wait in the past. Sometomes I am in a rush to deliver files to my clients so the long wait before the import can even begin is not helpful.

I don't remember needing to wait for all the files to be read in the past. I always have imported all the files on the card and the formatting the card in the camera after ecery shoot. 

Is this a bug?