I am in the process of applying for a job. The advert specifies the interview dates will fall during a particular week, but I am currently only available one day that week (as a result of national holidays and a conference in a different part of the country I am already registered to attend).
I assume the best course of action is to email the specified contact for the vacancy as early as possible to explain this and ask whether an appointment on the one available day is a possibility (or rescheduling to the following week), but I'm concerned that sounds like I'm being arrogant and assuming that I'll get an interview. Leaving it until later will either exclude me from the job (if it can't be rescheduled) or create additional hassle for the company (to reschedule). What course of action is likely to go down best with the employer?
(The advertised vacancy is with the UK civil service; examples involving this employer or similar will be most helpful.)