Originally Posted by CurrentlySober

Speaking from personal experience - unless stuff has changed - you can only stay for 3 months max on a tourist visa.

If you intend to 'overstay' Purchase travel insurance in the UK, that covers you for a couple of years. That way, you are covered if you need medical, but will have to pay for it at the time. You can however get a refund, when you return to the UK

IANAL - But thats just my thoughts

Enjoy!