Alter name of a property keeps the old property

When I alter the name of a property with

alter property MyClass.prop NAME "newprop";

then all my vertices of MyClass have the new property “newprop” with the right values, but also the old property “prop” with the original values (although the property is effectively renamed in the schema). Is this suppose to work this way? I expect the vertices to don’t have the old “prop”.