Removing a person from the register after death

Hello, my father-in-law passed away recently and I have a query relating to which form to use to notify this and to remove his name from the proprietorship register.

Some years ago, he added my wife (his daughter) to the register as a joint owner via the creation of a trust and we have a copy of the entry showing both their names as of the 16th June 2004.

Do we use the form DJP to remove his name (as the property is already in joint names) or do we need to complete AS1 in this case as my wife is the sole beneficiary of her father's estate.

My wife and I are the named executors in his will and we have obtained probate (if this is a factor).

Thank you.

Hello Geoffrey - I am sorry to red of your loss.
If the property is in joint names then form DJP plus a certified copy of either the death certificate/probate can be used to update the register re the death.
Form AS1 is only used if the whole of the legal title is being transferred from a sole deceased owner to their beneficiary. That can't happen here as the legal ownership passes to the surviving joint owner.
If the legal ownership is to be transferred to include the deceased's beneficiary then you would need the surviving owner to transfer the whole of the title to themselves plus the beneficiary as appropriate 
You can use our online assisted guidance to find answers and links to the forms/guidance needed depending on what updates are required - HMLR Guide: Start - External  · HM Land Registry