Confused Minions

I was playing a solo custom (no bots) on Summoner's Rift, Blue side, to check out Ekko.

I killed some minions in mid lane, and my melee minions in that wave pushed ahead and began fighting the next wave while my ranged minions just stood there, not doing anything. I'm not sure if this is some interaction with Ekko's kit or not. Anyway, my ranged minions began fighting as soon as the enemy minions eventually got in range.