She has been on medium rats for a few months now and takes them easily. I'm not overly concerned with size as the girth of the rat is slightly, if that, larger than her girth. However if you are talking about a live rat, then YES I would probably downsize for safety. She didn't stop her feeding until after her last rat X-mas day. From the sounds of things this is the normal time for the females to shut down. I just thought maybe this year since she is so young she'd continue through this season.
Thanks for the replies everybody.