X9 Plane Manager Bug?

[PKMills]

I am working on a milling part file in X9 and I noticed at some point that a plane called LATHE was created for me. There are no lathe ops in this part file and I don't see any toolpath that is using this plane in op manager, yet in plane manager it shows a check next to the lathe plane as if there is a toolpath using it. I try to delete it and it tells me that this plane is in use.

This is just a minor annoyance because it doesn't really affect anything. I was just wondering; has anyone else seen this happen or have any idea what caused it and how to delete this plane?

[gcode]

right click the plane and select info

it will tell you what the plane is used for

I'm going to guess it's stock related

did you import any geometry from a lathe file

[PKMills]

Aha, I should have thought of that. I must have inadvertently created a view sheet. This is something I never use. How do I get rid of it?
 

[PKMills]

There must have been a viewsheet created by someone else. I figured out how to disable it.

Thanks for the help gcode.