Note that the BUD updates when either a block is placed next to the piston, or when the redstone connecting to the piston and within the piston's chunk is destroyed. This redstone placement is unrelated to the one mentioned above, since we rely on chunk boarders hear.
FWIW, I like the idea of a BUD, but I fear that the way they are currently implemented (more of a side effect/bug of lazy updates than a feature) will cause more headaches than it will solve problems (kindly put, I'm in bugy/BUDy hell). I wish they would reconsider BUD as a bug and create a new BUD block.
Christopher McGinnis
In addition, this odd setup also acts as a bud, but relies on chunk boarders. (red/white should be in different chunks. Replace dropper with piston for better visual)
Image:
https://drive.google.com/file/d/0BxOpmZr8Qp5cSjRkNjBySHZ3WTA/view?usp=sharing
Scematic:
https://drive.google.com/open?id=0BxOpmZr8Qp5cb19nNC0yeWpqb0k
Note that the BUD updates when either a block is placed next to the piston, or when the redstone connecting to the piston and within the piston's chunk is destroyed. This redstone placement is unrelated to the one mentioned above, since we rely on chunk boarders hear.
FWIW, I like the idea of a BUD, but I fear that the way they are currently implemented (more of a side effect/bug of lazy updates than a feature) will cause more headaches than it will solve problems (kindly put, I'm in bugy/BUDy hell). I wish they would reconsider BUD as a bug and create a new BUD block.