Automatic dispenser does not always respect storage priority. In some circumstances, an automatic dispenser with a priority of 1 will generate errands to pull resources from a storage bin with a priority of 5. When the bin and the dispenser have identical resources selected, the dispenser behaves properly. When the bin and dispenser have different resources (bin having more resources than dispenser or vice versa) the lower priority dispenser will pull resources from the higher priority bin.
Both situations are identical except the bin on the right has an extra resource selected. The dupe (or sweeper arm) on the right continuously moves dirt from the bin to the dispenser and then from the floor back to the bin.
Steps to Reproduce
This issue has not been confirmed by a developer yet.