How soon you can apply for UK visitor visa

[ravisb_2014]

Happy New Year to all,

Hope everyone had nice time last year and looking forward for this year.
I am planning to apply for my father's visitor visa on August, 2018 but he is planning to travel on next year summer around April, 2019.

I wanted to know will UKVI accept visa application if you are applying 6 months before. I can't see any rule on this. please point me if there is any.

Recently I tried to create an online visa application for my father, it does allow for an application applying more than 6 months before. Not sure later if it fails or rejects as it just asks date of arrival to UK which is around 8 months later.

I will be really grateful if you clarify my queries please. Thanks in advance.

[vinny]

5. ECB9.5 What if applicant is not intending to travel straight away to the UK.

[ravisb_2014]

thank you vinny for your swift response.
As per rule, we can apply just 3 months prior to the date of travel or arrival.

Just curious to know - why does the online application allow you to enter future date beyond 3 months ?
In that case, it will be always rejected.