Thought I would pass this on from and it is expiring at Midnight UK Time:
I just tried it on a LG G4 and it brought the price down to AU $601.03 delivered (if people need a deal):
Easiest way I found was to search for the item on ebay.com.au then when you're on the item page, change the address to ebay.co.uk and follow on with that.
edit: turns out you can use it from the ebay.com.au site as well, thanks st33p!
Discount capped to around $98AUD in that case, based on a poor conversion rate.
Feel free to post any good deals if you find any as I don't have much time to search at the moment.
The limit as per link above is "Maximum discount of £50 (£250 spend)" and also limited to one transaction.