We do Seymor Narrows fairly often. Going through is easy at slack, no different from any other narrows but you want to be within the 1/2 hour mark. What is hard is to go through or come back without the against current slogging on one of the stretches. This year we rode
the tide up to the bay just before the narrows to port. There is great anchorage on the NW side but you have to go around a shoal that is marked by pilings.
We anchored there during the flood south then 20 minutes before the tide switch up anchor
I always get the beginning of the ebb going North, this push will last up to Race
and Current passage
if you are sailing, Helmken Island is a interesting stop.Coming back we usually ride the last of the flood going south but try to be an hour early to get some push to the next anchorage down. Leaving Campbell river before the ebb change figure on bumping against a 2-3 knot
current ant time to hit slack going North.
I love Johnstone Straight but if you are getting pasted the Northern routes are worth exploring. Turning at the Broken Islands and going up through Chatham is nice.
This year we came back through Okisolo and Lower Rapids then jogged through Hole in Wall to get in some Desolation Sound time.
Remember your BC tide books
are all in standard time.