Here is JJ China's reply:
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Pls send back to us to check and fix.
The Bearings is not under warranty, but if any other parts damaged we will replace a new one.
We will replace you a new CC for free.
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The CC replacement is because the glow plug sleeve disconnected before (you can read in an earlier thread).

Overall sounds like a very fair offer - what do you guys think ?

PS - is there a way to tell if these bearings are genuine GRW bearings?