I've never had one grow into the liner. Usually if you just grab the tuber where it hangs over the pot and tug, it will just snap right off. I'd be careful of my liner though. It might be rooted into the liner, but I doubt it. You might be able to feel around and snip each root with your fingernail without causing any damage if it seems rooted into the liner.
Good luck and welcome to our 'club house'. Come back and post some pictures and hang out with us.