If you check the terms and conditions on the upgrade program, I think you’ll find it is against the normal price of the device, not any sales price, so yes, it’s one or the other. 

Thanks Bruce.

Short and sweet!!

For others who have the same question, here is the direct quote from the terms and conditions, I’ve added the bold font:

Customers that redeem.... models will receive a Discount Credit equal to 30% off any one (1) regular priced product on sonos.com, with some product restrictions indicated below. Customers that redeem a PLAY:1, PLAY:3, PLAY:5 GEN2, PLAYBAR, PLAYBASE product, or certain CONNECT or CONNECT:AMP models will receive a Discount Credit equal to 15% off any one (1) regular priced product on sonos.com, with some product restrictions indicated below.

Boo 

Is there not a way to use the £100 festive offer and keep the 30% discount for another time? It seems I can’t choose which discount I want to apply and the upgrade one supersedes the £100 offer. I would like to benefit from the £100 discount this weekend and buy next year a Play 5 through the upgrade program...

Huh. I’d think so, but it sounds like it’s not working for you on the website. I would call the sales folks, and see if they can ‘force’ it through for you. Or maybe figure out away that you can do it on the web. 

@creeptonik, There is a way. Don’t log into your Sonos account, put in name and shipping address and other required data manually. If you are prompted to create an account, ignore/override it.

Edit: Put in the email address you’ve created your Sonos account with; the order will be associated with your existing Sonos account.

Thanks Smilja, I created a new account with another email address in the meantime before you responded . I’ll try to ask the sales team if they can associate the sales with the other account.

Edit: I was able to cancel the order within 1 hour and do as suggested, it worked :)

I am angry about this.  I just upgraded my Play:5 to a Move last week.  If I had known about this deal, I would’ve kept the Play:5 and upgraded it later for another speaker.  thought the upgrade was a good deal, but obviously not so good now.

It is a little silly: it means the upgrade discount is not a good deal after all.

Disapointing.

A lot of companies don't allow you to use multiple discounts in one transaction so it's not unusual. Also, trade-up discount is indefinite so you don't limit yourself to a few days each year when a product may  (or may not be) discounted. And the upgrade discount is still generally greater that any deal I've seen in their black Friday sale so it's still a good deal as far as I can see.

I’ve gone through the process.

I did the upgrade (only 15%) then realised I was better off getting the offer  £100 off.

You are able to delete the upgrade and then put it on later.

Happy:)

Frankly the upgrade officer is a bit of a joke then, don’t you think? If you can get a better offer when you don’t own a brick! Shame on you automatically offering “valued” customers the worst of the two offers when logged in. Poor customer focus Sonos