In final Cut Pro, will subclips relink if they get disconnected?

Trying to get my workflow down for an FCP project. Made subclips from master clips but tried exporting them and reimporting and they will not relink to the original media. What is the proper workflow here? Do I need to create new clips with media manager and edit with them? Problem is this is a film project so there is keycode information tied to the media- is there a way that that can be transfered to the new clips?