Readers' forum : ISA problem

I opened a first-time buyer ISA in December 2015 and was aiming to buy my first home when this had built up to a level to achieve the maximum bonus from the government.

My grandfather has recently died and left his half share of his freehold residence – held as tenants in common with my grandmother – to the grandchildren as tenants in common but allowing my grandmother to live in the property rent-free until she dies. When my grandmother dies she will leave her share of the property to the grandchildren as tenants in common. It is intended that the executors and trustees will then sell the property on the open market with the net proceeds split between the grandchildren.

I believe the trustees are the legal owners of my grandfather’s property share until my grandmother dies and there will be no income from the trust. I have...