Aphids can be easy to kill, or ..
. for some unexplained reason, they can sometimes be difficult. What in the world is in lupines that the aphids suck outta the poor plants that make them SuperAphids?!
Anyway, you have been doing the right thing. How about showing up 4 or 6 hours later, while 1/3rd of the critters are still enroute back to the plants, and spraying plants and soil with insecticidal soap?
I had not had wonderful success with neem oil in previous years but tried it again in 2016 on the aphids. It seemed to work best if I alternated with the soap. Either way, the aphids reproduce so quickly, you are probably needing to hit them twice several days apart, to give the plants some extended relief. Be careful to spray late in the day so the sun doesn't burn plants made vulnerable by the spray.
Best of Luck!
Steve