Well that could be absolutely anything!
Could be for a repair, where a request for a new jointbox has been requested when the repair is completed. They could have been pulling copper or fibre and encountered a blocked duct. They might then smash the duct open and fit a jointbox afterwards for easy access in future.
The indispensable man or woman passes from the scene, and what happens next is more or less the same thing as was happening before.
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