Silly question but need help lol.

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So at work we are taking pictures to put on a billboard on the side if the freeway. I'm going to get my hair done but the only appointment is Tuesday (day of pictures). Think it would be a bag idead to get it dye same day as pictures?? Or should i find a different salon? Im affraid the color will be to bold the day of and will need a washing. Mabye I'm over thinking it. Inputs??