If you're getting FBA, it's just an optimization of throughput. If there's enough folks in your area with Prime, trucks are going around your neighborhood daily anyway, so it's better to send a full truck, even if it means things get there early, then to send a partially empty truck twice.
Amazon likely does not have separate Prime and Non-Prime lanes in their warehouses. It would be a redundancy and add additional complexity that would increase costs/reduce profits. Since customers never see the warehouse there really wouldn't be any benefit to doing this.
Are we in the game where an event happens randomly, and we’re trying to guess whether any of our actions, if not worshipping Bezos directly, might have an effect on delivery times?
There's a lot of existence that really feels like we just live in a hash code now. And its all malevolent for some reason. It feels like there's "supposed" to be something you did wrong, yet it's all malevolent hash randomness. Maybe all the focus on cryto money?
That, or we're being experimented on. "What will the mice do if we poke them this way? The ants really hate it when we shake them this way."