The pun is from 危うい (ayaui; dangerous) with "ui" changed with "nui" from "Shiranui" cannot think how to translate it in english. the closest migh be Nuisance, but that has different meaning.
I can hardly call myself a translator, but I would think that nuisance would describe a closing deadline. Although you should definitely get a second opinion on that.
The pun is from 危うい (ayaui; dangerous) with "ui" changed with "nui" from "Shiranui" cannot think how to translate it in english. the closest migh be Nuisance, but that has different meaning.