UK Ancestry ILR - Can you change the Grandparent?

[Im_Phil]

Hi,

MY girlfriend has recently applied for her ILR following 9 years living in the UK an an ancestry Visa which was applied for using her father's father as the grandparent. However, she was unable to continue with the application as her father has lost his original birth certificate and getting a replacement from her home country (Zimbabwe) could take a great deal of time.

She can also claim ancestry from her mothers side, for which she does have all the necessary documents in place. My question then - is it possible to change the grandparent through whom you are claiming ancestry when applying for ILR? The UK Border Agency simply told us to get a lawyer, which will of course be quite expensive.