I hope they are able to get it fixed for you soon, As you know, I know exactly how you feel.
I'm really lucky to have a great bunch of guys in the store I got my bike from, as even after my last service, my rear cassette just keeps slipping as does the chain and motor is "clicking" when I put a load through it.
So now they are just exchanging the entire bike for a brand new one (mine is less than 30days old though)
I'm expecting a delivery this week of a brand new, unused fully boxed Carbon Expert so fingers crossed this one will be more reliable than the current one as the bike is absolutely incredible.
I'm not getting a 2019 model, but I'm going to upgrade in the summer next year to a 2020 model, and my other half wants one too,
so we will for sure be shopping with the same store.
Sure supporting a local store is great, but when you get support and service like that, from a non local shop, well... I'd rather take the slight inconvenience of delays in getting things fixed, but with knowledge of hassle free, fast, prompt amazing service.
I hope you get the bike sorted and keep us posted with what it was and how they fix it etc as it could be useful if others run into similar issues.