Damn, I just lost everything I wrote. Please get EEVBlog up to the 21st century.
Theres no way of knowing what the rates are till after i move in.
That is no way to do business. Not even Elon Musk would sign a lease without knowing what it would cost. If that is London today, it's sad.
1) Sign the lease with the landlord.
2) In all probability, you will get the exemption and be in clover.
3) If not, just don't pay the addition tax. What's the worse that will happen? You lose the space sounds reasonable. Nothing gained, nothing lost. Perhaps you go to prison. Debtors' prison may still be in vogue in London. How about daily floggings?
4) Worse case, that could be the longest time you have held any job/position.
Going back to my post #25, it seems you're looking for an excuse not to deliver on a product you promised. Assuming that's the case, just move to a new life where we don't have debtors' prisons or floggings. Garrettsville, OH is a nice place, and it's close to a small college where you might find a job teaching (Hiram College).