Re: What are my rights to rent a flat forward?
You need to check your contract, but usually the rule is that you have to find 3 suitable applicants for the landlord to chose from, otherwise you will have to pay the rent for the outstanding months. Also check the actual notification details - is it just to give your landlord 3 months' notice at any time of the year or is it 3 months' notice before the official moving days? This can make a difference if you official days are 30th June and 30th September for example.
Have a look at the FAQ in this section which has several other threads about tenancy agreements and termination of contracts.