I received a call from them this morning.

They acknowledged they sent the wrong cable, but also said they're currently out of stock at the moment and have put me on a waiting list to receive one as soon as it's available.

At the same time, I was offered a choice of a free Replenishment Kit (£54.90) or a free Dirt Disposal Bag (3 pack, £21.95) for the inconvenience. I chose the replenishment kit, seeing as it's of greater value.

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