Thanks for your question. I will try to help.
Unfortunately your grandmother holding a UK passport and UK citizenship does not afford you any additional rights in respect of your Tier 5 visa.
A Tier 5 visa is a visa completely independent of a person’s ancestry.
The ancestry visa has made as a concession to commonwealth persons who had a grandparent actually born in the United Kingdom.
The rules are applied very strictly in this regard and if your grandma or grandpa was not born in the United Kingdom then you are correct in determining that you are not eligible for an ancestry visa.
You can not of course extend your Tier 5 visa beyond two years and so if you wish to explore your options for staying in the United Kingdom then probably the most sensible thing to do would be to look for a job for the purpose of a Tier 2 general visa.
Here is the link to Tier 2 general visas:
You would have to find a job from an employer sponsor willing to sponsor you for this purpose and firstly check to see if there is a job on the shortage occupation list;
If there is no job on this list then you would have to see if the employer is willing to confirm that there are no members of the residential labour force willing and able to do the job at the salary offered.
If you were to secure a job offer and meet the eligibility criteria then you could apply for this visa, but you would have to apply from outside the United Kingdom because switching into this visa from within the UK on a tier 5 visa is not permitted.
I am sorry that I could not have better news for you.
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