I've been waiting on a new trek road bike since last Autumn, I call the dealer once a month or so, every time I call, the ETA is put back another month or two. They can't/wont say the exact cause, but they are hinting it's component shortages. I needed a new 12spd cassette for another bike recently and was very fortunate to find a store in Spain with stock, I bit the bullet and paid the extra postage (about £6) as nowhere in the UK had any at the time. I signed up to a bunch of stock alerts with the big stockists, not one of them have pinged yet so looks like I was lucky and made the right call.