[oh8eleven]

I can't sign up yet because I currently have coverage with my employer.
I was already on Medicare (Medicare Advantage actually) when I signed up. Having insurance should not prevent you from applying.
In fact, I worked with a number of vets who had healthcare insurance, but used the VA for their prescription drugs. Much cheaper.
You mentioned your "VA rep." In my area, our county government has a small number of county employees whose responsibility it is to act as veterans' advocates, to represent and guide them in obtaining benefits and services.
I suggest you go to your local government's website to see if they offer the same/similar service.

[Diana in Wisconsin]

Yep. Already have! :)