1. Yes, just your passport and biometrics appointment letter. I don't think you even need the application, but there's no harm in taking it as well.
2. Yes, that's correct - although you do need to be able to provide the evidence if they ask for it (I.e. you can't just say you meet the requirement - you need to prove it if requested)
3. Not sure - we haven't had many people applying for student visas this summer, and most usually people apply in June or July.... late-August is quite late for applying. It depends how busy they are and whether you pay for priority processing or not. Back in May, most applications were processed within 3 weeks, but we don't have any updated published stats yet. As it's 19th August already I would recommend paying the $250 for priority processing as we have seen some student visas take up to 2 months to be processed in the past and I assume you have to be in the UK to start the course in September?
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