So I missed the paragraph where you can, in fact, accelerate the work at a slight increase to the DC. Poo.
Just goes to show that your ultimate client is just as unfamiliar with how magic item creation works as the DM.
It does still take most of today's day chunk to finish up the item, and combined with meeting with Mr. West again and say, taking a break for lunch because why not, Dalen will be in the evening portion of today after the item is created - and 1,500 GP richer.
Does that match your expectations?