FYI @Brad_ST I had the same issue. I had one virtual switch that was listed in the classic app but did not show in the new app. After doing a inventory of simulated switches I also found I had one switch shown in the New app that was not in the classic.
I then realized it was a switch that I had renamed in the classic app. It was still showing under its old name in the new app, but showing the new name in the classic app. The old switch name listed in the new app did not show up in the IDE however, only the name in the classic app.
I wasn’t 100% sure that was the case because turning either one on or off did not change the other.
It wasn’t until after I created a new switch and moved my automation to the new switch and then deleted the old virtual switch in the IDE that I was sure.
When I deleted the switch name that was shown in the classic app from the IDE the banner after it was complete said that it had deleted the old switch name that was shown in the new app. I hope that isclear.
I got mine sorted out but I thought I would mention it as something to look out for.