A pistol can always become a rifle. Rifles can’t become pistols - with a few specific exceptions, the TC’s being one of them.
A “kit gun,” such as the TC’s, even sold originally as a rifle, can always retain their kit gun capability as they were originally designed and manufactured to be both pistol and rifle.
As long as an Encore or Contender are not assembled as a short barreled rifle (barrel < 16” with a shoulder stock), they can infinitely be converted back and forth among rifle or pistol configurations.
https://www.atf.gov/file/55526/download