Topic: NS Digital / physical linked?

So quick question that I don't know if it has been answered or not and prob dumb but I rather ask anyways.
I was wondering if I got a physical copy of, let's say for example, legend of Zelda Bof, and I want to ditch the cartridge and go digital, will I have the same save date ?

Your save data is saved to the console, so yes. Your save data will be unaffected.

Switch cartridges are read-only, just like the disc-based media that preceded it, so they are incapable of having data saved to them. This also helps cut costs as read-only media is cheaper to produce than rewritable media.