A design change was made to the Avionics Bay and the Payload area of the rocket in order to better constrain the avionics and payload bulkheads while not loading the piston from the back (by the payload bulkhead).
For the payload bulkhead, this change led to the possibility of bolting/riveting the bulkhead in place from the side and through the nose cone or body tube. This allows for the payload to still be fixed in place and act as a support structure for all the hardware in the nose cone while not relying on piston to hold it up. Because of this, the piston is free from the load of the payload bulkhead as it will NOT be fixed to it.
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