Yeah I'm actually surprised the company didn't work with you on this one; was the requested delay huge? In any case it sounds like you made your choice, so good luck.
No, I was flexible to any time they could suggest before or after interview, they said it was a tight recruitment deadline though.
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Just an update, had the interview I *thought* it went well and went to (end of the)conference on that day. I also went to GI.biz summer party (was great) and I actually spoke to a guy that worked there. He wasn't in the same department but offered to put in a word for me with the people in the right department (although I couldn't remember my interviewers name *facepalm* ).
Anyway it will be a week tomorrow and still not a word :( seemingly unlikely I got the job. Got to live in hope though I guess...
Thanks for the suggestions!