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So I'm a new graduate who took months to find a new job. Recently I interviewed, and was very quickly hired, for a semi-decent job which I was more grateful for getting than anything. The work culture is very relaxed and the team are super friendly and accommodative. I've been at the job for a week, and now a really amazing company, with a better salary and position I'm more passionate about invites me for a final round interview in a different city. There's a very slim chance that I could get the position.
So my question is how do I go for this interview in another city seeing as I have no leave (etc.), and if I do get the position, how do I break it to my boss whom I really like?