There is no need to wait to remove the Ceramic Coating and re-apply. You can do it right away. You will, however, need a polisher to mechanically remove the coating since it is now fully cured and can't be simply washed off. If the hood is the only really noticeable area with scratches, there's no need to remove the CC from the entire vehicle, though.
It's not an easy task, but on the upside, in the process of removing the CC, you'll most likely compound out the scratches that bothered you in the first place.