From the Star Wars brand team:

We have noticed on some boards that some collectors are deciding to wait until the Target-exclusive Order 66 sets go on sale before pouncing.  This year, Target has advised us that the order 66 sets will not go on sale when they come off the checklane endcaps and will extend at regular pricing in the planogram.  We think that those fans waiting may be disappointed when the ones they want sell out.  If there are certain army builders or characters that collectors had their eyes on, they might not want to wait.