If we're talking about authorized dealers, dumping product ahead of an official announcement. That would be a no-no with most of the big guys. But in this economy, I wouldn't bet against a few jumping the gun.
However sometimes shops decide to end relations with a given mfg or visa versa and often in that case, all bets are off.

I don't think any of this will come as news to anybody..

Won't confirm or refute the practices of other shop management. However, I would often spend my early morning coffee time perusing the fly fishing forums ( for many reasons ) where almost inevitably, somebody connected to a manufacturer, or a "well connected" shop owner or employee would jump the gun with the news of a line being discontinued.

Or they might come forward with an early announcement of a new product launch that would be an obvious replacement at a given price point and performance package. By themselves, those indicators aren't always worth acting on, but if the product line in question is getting long in the tooth. Then some market refreshment might be on the horizon, especially if the mfg. in question has a track record of roughly X number of years per product run.

Now I'm not saying that you should believe every rumor you read in these forums, but things do get posted by insiders that sometimes indicate an approaching change, well in advance of an official announcement.

Sometimes separating the bull from the bullion takes a trained eye, but the information is usually out there if you know where to look.

Best, Dave