I finally picked up a copy of this (I have the previous Arrow Blu-ray) and watched both versions the other night. Found something odd that I don't remember noticing before in the end titles.
In the 4K version of the Theatrical Cut, there's a list of three dubbing voices for Philippe Noiret, Jacques Perrin, and Bridget Fossey. In the Director's Cut, just as those three credits start to come up, there's a 5-second cut that jumps to the next credit. So I pulled out the previous Arrow edition, and that cut appears in both versions. How odd.