When you speak to a faults agent, they'll run some remote checks to establish if there's any known issues in your area, or possibly if they can see a box and/or network issue remotely.
In most cases, if there's no network issue apparent, the result should be a tech visit to have "hands and eyes" on your installation and the streetcab, and then take whatever action is necessary - which may include a boxswap. There are occasions when a box-swap is offered immediately, and it sounds like that might have happened here.
You can wait for the forum staff to pick this post up, but be aware their response time will be a few days, and adding further replies to this thread can potentially drop you down the list. If your box is diagnosed faulty and needing replacement, then you're correct to say you'll lose all recordoings. That's the nature of the beast I'm afraid.
I'd recommend starting to make a note of which recordings are available from other sources, such as VoD. Watch those that aren't.
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