Firstly congrats on getting a job ive been trying for a couple of years now, its still very hard out there and the whole job hunting process had changed so much very much harder for old school people.
echoing really what others have said better off not telling your new employer about it. Trying to arrange an out of hours meeting should not be unuasual,or ask to put the interview to a later date so its not so close tou your start date. But if not you can only tell your employer you have a prevoius comitment you need to sort out and try and get the interview for 1st thing or last thing at night.
the age of being totaly honest has sadly gone , you need to look after number 1.
But at the end of the day whatever you decide worst case senario you have a job and i do belive its easier to get another job when you are already employed besides there is a chance your employment could be extended
all the best with it Pete well done
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