ANyone know any low cost Canada flights in the evening? (esp 1/30 or 1/31)

(LAX-YVR at $80~ does not run in the evening on 1/30 and is expensive on 1/31)

Why? I am going BDL-IAD-FCO-IAD-BDL and on the return (FCO-BDL-IAD) if I squeeze the canada flight on the same day as the FCO-IAD-BDL it will give me an afternoon flight BDL-IAD.($407rt) But... if I do the canada flight the next morning, to get the same price I must wait around for IAD-BDL at 10pm. Taking the earlier flight is more in that case.
(Logic, if any? I guess because if I take an afternoon flight to BDL and then next day LAX-YVR it then thinks I am having a stopover at BDL, whereas if I take the last flight to BDL and then an early morning canada flight, or all on the same day, no stopover???...disregarding that BDL and LAX are 3000 miles apart)