You need to contact Shelter. I am on the tenancy matters UK on Facebook and they never recommend CAB. They say they give incorrect advice and don't enough about housing issues. The Facebook group give excellent advice.
For a landlord to evict you, they need a section 21 which gives you two months rights to move out. This is when you can apply to council.
Quite lightly you will be fine and the new buyer will want you as a tenant. Just make sure you read up on your rights.
I also sold my house and started to rent, it is the worst thing I could have done as there is no real protection in renting as you can be asked to leave at any time.