You want box or digital?

Yes, you need to buy the game first, will free 30 days for you, after 30days then the subscription starts.

as for your question about GBP, why you must buy it in GBP may i ask? isn't that limiting your choice? or you misunderstood that you need to buy in GBP to pay subscription in GBP? Because,
1 - that doesn't affect your currency in subscription as long as you bought an EU version which gmg offer if you're not in US. (they do show it as US dollar but it's EU version for us malaysians)
2 - registering an EU Square Enix account, and selecting United Kingdom as your country, will put your subscription currency in GBP if this is what you're aiming for.
3 - fake address doesn't matter as long as there's way to pay the subs monthly, and that you remember that address you put in. Because when unforeseen stuff happen to your account, you will need your name, game id, DoB, address to submit to the tech team to validate your the owner of the account, and again, telling them it's a fake address doesn't matter.

When you buy from GreenManGaming.com, you will get the EU version, but the initial price they charged you is based on USD. The key they give you will however be for EU version.

restart?

can you post your own screenshot... hard to determine what you mean.