I gave my malepositioned chick 18 hours to make progress, when no progress was made, I increased the hole to get an idea of positioning. In many cases malepositioned chicks make it out all on their own, in my case my little gals position was so bad she would not have been able to get out as she couldn't turn to zip or push at the shell because her leg was over her head and her foot was rested on the beak (coming from over her head.) Literally her beak and toes were sticking out the pip hole. I increased the hole a bit and then returned her to the bator to see if she could make progress, when after a couple more hours she could not I started the zip line. (I did this a couple times each time giving her chance to make progress herself. Once she was able to get her foot back down and in position to push, she finished the job by herself and is a healthy almost 4 month old pullet now.
So I'd give her 18-24 before deciding anything, and then it would be to widen the pip and check her position. If she was in a good position I'd put her back in and give her more time. If she looked like her positioning was way off I would start to help, but give her time between helping to make her own progress. If you see a significant amount of blood, stop. If you see unabsorbed yolk, stop. Hopefully she'll make it out on her own though. Good luck.