Can't make use of discount code on upgrade program

[hipwell]

Well I've held off upgrading on my upgrade program for the s25ultra only to find that the discount codes for the 10% off don't work via the upgrade lounge, only if you order via the app which has the App25 code which works.

So yet again now the upgrade program has ended, we get shafted again because we can't make full use of the discount codes. 

Anybody got a workaround for this? 

If I order via the app shop, my £100 off voucher and the 10% off work together along with the free buds 3. But not via upgrade lounge. 

[Glenntech]

The upgrade program has basically ended now.
So you will need to go through a different purchasing option now.

[hipwell]

I can still upgrade through the upgrade lounge, says existing customers can still upgrade