Evidently so. I see discounted prices on bundles, having done a Trade-Up.

Only from sonos.com.

Single products only, no bundles.

Articles claim it will be available at Best Buy and through licensed installers, but for now I believe it is just Sonos.com. 

Strange, the FAQ says otherwise.

What can I purchase with my Trade Up credit?

Trade Up credit applies to a single product purchased on sonos.com, excluding limited edition products, refurbished products, and third-party accessories.

https://www.sonos.com/en-us/tradeup

Hmm. Maybe an ‘error’ then?

Hi everyone, the 30% trade up discount can be applied to a single Sonos product (some bundles are currently being treated as one product for these purposes). This cannot be combined with other promotions or discounts. Discounts for product sets will be calculated from the full retail value. Gift cards, third party accessories, and refurbished products are not eligible.

Hi Michael

I don’t know where you are in the world; however the retailer in the link is offering a 30% discount to recycle your Sonos. I’m not saying it’s the same as the Sonos promo; but the eligible products are similar. It appears to be a simpler process...meaning no shipping required:

https://www.bestbuy.com/site/conditional-offers/sonos-recycle-offer/pcmcat1570646177493.c?id=pcmcat1570646177493