Thanks for replying @Mike-And-Helen0, I managed to find this which at least resembles some sort of policy terms & conditions and here's the link incase anyone else finds themselves in the same position.
https://www.airbnb.co.uk/help/article/2869/host-guarantee-terms-and-conditions
But the policy document totally contradicts the Airbnb website in terms of contact with the guest prior to making a claim. The Policy says you need to ask the guest for money first before making a claim but the website says you don't need to do this because Airbnb will do this for you. See screenshots
In my case, the 'guest' turned out to be a drugs gang who took over my property (where was Airbnb's precious ID verification one has to ask - they were known criminals) and I had to get the police involved. We were literally cowering in a car round the corner watching the on the doorbell camera too afraid to go anywhere near them until the police arrived. It has been a truly terrifying ordeal. The flat was trashed. Police advised me that more recently drugs gangs have been using Airbnb properties for coming in from outside areas to deal. Not sure whether this is restricted to London or it is in other cities but I urge UK hosts to be on the look out.
Also noteworthy for hosts is that we discovered only after changing the locks and having 7 hours of professional cleaning that there are various caps in place. The cap on the lock change is $500 which did not cover the cost of the Banham Banham windows and doors. There is also some condition in the cleaning reimbursement which means they don't cover products. In our case product to remove the smell of all the drugs (Class A) and left over fast food. This was declined by Airbnb.
Airbnb have been next to useless in dealing with this. Infact I'd say their behaviour has bordered on unsafe and irresponsible. So much for their Ambassador who according to the website is supposed to guide you through the process. I have simply had emails that avoid answering any of the questions and this morning I've just been emailed saying they need proof of my identity before they can provide any help! Seriously?! I mean no problem - they can have passport copy pronto - but they were happy enough to let a drugs gang into my flat but need my passport to help me resolve all the issues I've been left with as a result?! I sincerely hope they have passport copies from the drugs gang and lets hope they assist the police with this. But now it appears they then want me to start corresponding with the drug dealer otherwise they won't validate my claim. This includes sending receipts on with my home address on it - something I really really don't want to do. On the phone 10 days ago they agreed this would indeed compromise my safety and I didn't need to do it but now they've stopped communicating in any tangible way and I have a nasty feeling they will decline my claim on the basis I didn't ask the drug dealer for money directly before issuing a claim.
It is truly a horrendous experience. So please UK hosts out there - take care.