Looking for Ferry Info from Nanaimo to Tsawassen on May 21

[Samw]

Its too late to make a car reservation now for an evening sail back from Nanaimo to Tsawassen for May 21 this long weekend. How many sailing waits do you think it will on May 21 to come back to Tsawassen? Would it be safer to drive to Swartz Bay and take that ferry? How many sailing waits are expected at Swartz Bay? We are kayaking until 2:30 so we probably won't leave Tofino until 3pm. Will we be stranded?