11.K    The Net Posts.  The net posts (including permanently attached net adjustment handles and winch) are positioned out of bounds.  It is a fault if the player or ball contacts the net post while the ball is in play.   Net post legs, wheels, removable adjustment handles and other support structures are not considered permanent objects.  If after crossing the net a ball in play first bounces on the court and then contacts one of these support structures a hinder shall be called and a replay shall occur.  If a player, a player’s apparel, or a player’s paddle contacts one of these support structures while the ball is in play and said contact interferes with play a hinder shall be called and a replay shall occur.

11.K.The Net Posts. The net posts (including connected wheels,
arms, or other support construction) are positioned out of
bounds. It is a fault if a player contacts the net post while the
ball is in play.

As written, the rules specify net posts, net post legs and any support construction including connected arms or wheels as permanent objects, and as such are positioned out of bounds.  It is a fault if a player or ball contacts any of these structures while the ball is in play.

The standard reference net post is a vertical post no more than 3 inches in diameter with the inside of the post positioned 1 foot from the sideline.  No attachments other than the net assembly are addressed in the net post description.

A player should reasonably expect to have the right to play on a court based on the standard reference net post.   Any other attached structures that can potentially interfere with player or ball movement should be considered a potential hinder.

1. A ball in play crosses the net and strikes a net post support bar before bouncing.   The ball is called out by rule.  Whether it subsequently lands in or out makes no difference.
2. A player hits an Erne and his shirt makes contact with a removable net adjustment handle that was not removed prior to play.  Play continues, this is not a fault.
3. A player attempting an Erne trips over a net support wheel.  A hinder is called and a replay granted.
4. A player returning a wide dink makes paddle contact with a net post support bar.  Play continues unless the player claims the contact affected his shot and requests a hinder, in which case a hinder and replay are granted.
5. A player attempts an ATP.  The ball strikes a permanently attached net adjustment handle or winch assembly.  These are part of the net post, therefore out of bounds, and a fault is called.
6. A player attempts an ATP.  The ball strikes a net support bar or wheel.  This is a fault, as the ball had not crossed over the net.
7. A player attempts an ATP.  The ball brushes the net cable on the outside of the net post between the top of the net and the winch assembly.  Play continues, as the cable as part of the net system and not the net post.
8. Player A  steps out for an Erne but the opponent dinks to his partner who pops the ball up.  Seeing the opponent about to hit a winner, player A kicks the support bar and claims a hinder.   The referee declares the hinder invalid because the contact did not affect play, resulting in a fault on Player A (rule 7.M).