Get Sharing Link - layer ids change?

I wanted to be clever and use the Get Sharing Link to generate quick urls to use from other resources (like our public website) instead of creating workflows that query for the layer.  For instance, from X Fire Service Area webpage → open viewer app with the layer for Fire Service Areas turned on.  Sadly, the id is not static?  What was once (for instance) &layers-default=36 is now &layers-default=38?  I don't even remember pushing anything new to production that would remotely have to do with the layers.