Who owns the property

My Mother was sole owner of the house and died without a will. My Dad applied for letters of administration and inherited the house as her spouse and the laws of intestacy. He didn't update the land registry and died last year. I have only found out he didn't update the land registry as his executor so have had to apply for grant de bonis non to sell the house. None of this is a problem other than council tax are now saying it is my mum's house and are charging full council tax for the year it has been empty including a double charge for the time before it was cleared as they will not accept dad became the owner, he has been on the bill since Mum died and paid the council tax. My query is if you inherit a property via intestacy laws do you own it despite what the land registry hold?
Thanks

Rachel - the property remained as part of her estate until her administrator actually transfers the legal ownership to her beneficiary/successor in title. Inheritance alone does not transfer the legal ownership hence the need for you to obtain the grant de bonis non to create what's known as a chain of representation and to allow you, as your late Father's executor, to now transfer the legal ownership