Intended date of arrival in UK

[coorgi]

Hi there,

My course starts on the 23rd of September 2019 but I would like to come early as early as I can to get acclimatise and get to know the place and culture better before I start my course. I am applying for the visa next week, can I mention 25th of August which is 30 days to the course start date but my agent is asking me to enter 15th of September. What would be the entry clearance date if let's say I apply next week and I get my visa granted in two weeks. Why should I not enter the earliest date that I can legally enter the UK.

[CR001]

https://www.gov.uk/tier-4-general-visa

How long you can stay
You can arrive in the UK before your course starts:

up to 1 week before, if your course lasts 6 months or less
up to 1 month before, if your course lasts more than 6 months
How long you can stay depends on the kind of course you’re doing and what study you’ve already completed.

[coorgi]

https://www.gov.uk/tier-4-general-visa

How long you can stay
You can arrive in the UK before your course starts:

up to 1 week before, if your course lasts 6 months or less
up to 1 month before, if your course lasts more than 6 months
How long you can stay depends on the kind of course you’re doing and what study you’ve already completed.

Thanks my course allows me to come 30 days before but the agent was suggesting that if you say a month before then home office my question your intention to arrive much earlier than your course start date. Would this become a problem as I would be staying with my sister. I definitely want to come as early as I can and I would prefer to mention the earliest date of arrival as long as it wouldn't risk my application. Would this risk my application?