Looks like the shop needs to do their work again unless you think they are incompetent in which case, you'll be doing the work and asking for a refund. These brakes are just like every other system that has solidly mounted calipers.

New wear sensors are readily available as are hoses. Not having wear sensors is not really a problem if you are attentive to maintenance. We were able to change brake pads for many years before the electronics began to allow sensors on every little thing.

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.