A few years back we brought our son's boat from Shilshole to Anacortes via "the ditch", we left Shilshole around noon, stopped at Edmonds for fuel, and arrived at Anacortes near midnight if I remember correctly. We were surprised to be able to find fuel at that time of night in Anacortes. We were fighting some tide the whole way. This was part of a 31 hour trek Tacoma to Vancouver.
So I'd guess unless you had more favourable tides you're looking at 10-12 hours anyway.
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)