We can't answer that as we're members (paying customers) like yourself and aren't given info about stock levels.
All you can do is keep an eye on the site regularly to see if/when the iphone 7 plus comes back into stock.
@tellebum, hi there, thanks very much for your enquiry about the iPhone 7 Plus. Regretfully, Giffgaff do not supply us (giffgaff members) with information on the stock availability of the phones giffgaff currently sell, other than what's currently displayed on the website in realtime.
I am sorry that it is out of stock at the moment. All I can suggest is that you visit the link I have listed below regularly and hopefully, you will be able to purchase your iPhone 7 Plus from giffgaff very soon.