I'm on my way to get serious and start having the need to gather all my stuff in one big storage room, so I'm planning to use smart splitters (I don't have access to programmable ones yet). So my question is, given a smart splitter where

Input - Anything

Left output - Selected item to storage

Front output - Anything but selected item (to the next storage)

Right output - Overflow to sink

Once the left output is blocked, will the overflow gate send only my selected item to the sink or it will send anything that passes through the splitter?

In other words, what's the hierarchy or order in gates? Clockwise left-front-right will work and send only the overflowed item to sink, counterclockwise left - right - front will send anything to sink because items won't get to the front gate.