Hi Ali,
I think the delay in getting my replacements was due to waiting for the new improved version.
You could try checking that they have some in stock before sending yours off, bear in mind they go to Ireland and that cost me £20 via courier.
Recorded delivery may be cheaper but I wanted a quicker turn around - ironic or what?
I would get them replaced if I was you as they are still under warranty. Whether the new version fixes the problem is not clear to me as the strain reliefs appear very thin at the ends, once the split starts that is it.
I have a pair of old Philips earphones with strain reliefs. The plastic they use is a lot more rigid and I think standing on them would not cause a problem. That said they are not even close to the sound generate by the X10s. Good luck Hammy