Originally Posted by Gerkraz
Just out of curiosity, and I'd like an honest answer, if legislation changes turning an previously legal object into an illegal one, is there generally a "grace" period where previous owners can turn these objects in without fear of legal persecution?
To answer, yes there is. Usually it is a set date from when the legislation was confirmed.
Take the smoking ban in Toronto for example with restaurants. They had x-number of months to (at first) revamp their air filtration and HVAC systems so that they could have a designated "smoking room" and at a later point, the full ban completely.