Put the summary of the bug you're having here
Hopper won't move potions into brewing stand if it's connected to the side
but it moves blaze powder instead

What I expected to happen was...:
The hopper will keep moving unless powered or all the slots are filled

What actually happened was...:
The hopper connected to the side of brewing stand will stop moving potions, instead, it moves blaze powders to blaze powder fuel slot

Steps to Reproduce:
1. Place a brewing stand
2. Connect a hopper to the side of brewing stand
3. Put potions into the hopper and take them from brewing stand and repeat a couple of times
4. Place a hopper beneath the brewing stand and repeat step (3.) but take potions from hopper beneath brewing stand instead of brewing stand

NOTE: doesn't matter whatever both hoppers are powered by redstone or not