The shop took it 100% on the chin. Worked at a shop for almost 4-years and of the 7 manufacturers we carried during my time there they all worked the same.
Most of the manufacturers would start to clear out back channel inventory in late February / early March. So for example, if you wanted a Domane SL 6 in the less popular color (because there's usually two) in an odd size, sometimes it was impossible or very difficult to get you one after about Valentine's Day. Typically the shop would pre-plan the year in August/September and get access to the upcoming model year's lineup (specs, colors). The more you bought up front, the better the pricing. Some manufacturers require you buy X of Y.
I've worked PT boutique retail for almost 20 years, from my experience, this was all pretty normal stuff, so not specific to bikes.
Where the real deals occurred is when manufacturers would do blowout sales at wholesale before the model year transition. For example, one we brought in DA Di2 (9000) bikes from a manufacturer for a hair over $2400 and sold a half dozen of them at almost $7500. Ironically, there's a Giant Defy from 2014 in the shop that has never sold.