Correct, it really depends on the type of change you want to make. If you simply want to update the estimated arrival time, make a special request in the comments, or (in most cases) even change the number of guests from 1 to 2, that won't make any difference.

But if you change the dates, the confirmed bed type, or something else that affects the rate and/or is subject to current availability, then the new terms (including any cancellation penalty) will almost certainly apply.