Deceased Mother on title register

Good morning, looking for some advice if possible!

My grandmother has recently been put into full time care and my aunt and uncle who have power of attorney are selling her house.

There are 4 names on the title register, my grandmother, aunt, uncle and my mother who is deceased. There is a form A restriction on the register and from what I've read, this indicates they may be tenants in common but I am unsure of this. Is there a way to check this?

If they are all tenants in common does that mean my mothers share should be passed to myself? I am the sole benefactor of her estate. My uncle has recently asked for a copy of my mothers death certificate so I am assuming they are removing her name from the register.

Any help would be much appreciated!

G M Lauren - a form A restriction is often regarded as confirming that they were TIC but the register is not definitive on that specific point. Our online guidance explains more.
We don;t deal with the specific beneficial shares so can't advise you on how they should be dealt with but from experience that's how it should work. 
If it's being sold then they will need a copy of her death certificate as evidence for the buyer as to why your late Mother is not a party to the transaction.
If you are unsure as to your beneficial rights/what happens re the estate etc then please do seek legal advice/reassurance 

Thank you for your advice, have a good day!