I spent 2.5hrs speaking to Apple at the weekend because of this issue...
I bought my Series 8 with braided loop in January. Just this past week I noticed that it was no longer fitting properly and it was sliding around my wrist. Very unhappy about this, I contacted Apple support for a replacement or repair as it was less than 6 months old.
I originally went to the online chat through the Support app on my iPhone, I spoke to an initial agent and then was transferred to a senior advisor - but was eventually told that I would receive a call back from the support department.
Apple refused to replace or repair the strap. I was transferred to a senior technical support rep, was told again the same thing that Apple "would not be able to replace or repair the strap". He asked to see photos/videos of the strap, so after sending me a link I uploaded them... He then said there was no physical damage or defect, but could still not replace the strap as there was nothign wrong with it(!?)
I quoted this to him from Citezens advice:
"Under the Consumer Rights Act 2015, goods should be of a satisfactory quality, fit for purpose and as described. My rights have been breached because the item you sold me is faulty/doesn't match the description. I would like a repair or replacement.
He tried advising me to go into the store, as they *might* be able to do something(?!). The store is 1hr drive away. I explained that I did not need to go to a store, I bought the watch online and so with distance selling regulations they had an obligation to resolve this as the item was faulty. Plus, with no guarantee that they would do something in store I wasn't willing to take the chance. He offered to transfer me to the after sales team.
The After sales were really apologetic, they explained that there was literally nothing they could do as it was a technical support matter. They were very nice and re-transferred me back to the technical support team.
I was speaking to this person for all of about 2 mins (after re-playing the whole story for the 5th time!) and was immediately transferred to a Manager.
6th time's a charm...!
After again reiterating that it is my right under the Consumer Rights Act 2015 to seek a repair or replacement for an item of unsatisfactoryu quality and which is no longer fit for purpose - I was promised a call back later that day.
Finally, I was called back by Apple in the afternoon and they have upheld my request, and are dispatching me another watch strap.
I discussed with the person whether I should change it from a Size 8 to a Size 7 and she acknowledged that it should not be necessary as there is clearly a fault with my strap. If the same thing should happen again then I need to contact them again - this could be Apple's way of not admitting there to be a problem but at least, now i am happy!