When you say you scan, do you mean you are a SPA scan-print-apply labelslapper, or a do you scan while loading a trailer?
Strictly speaking there are no "skilled" or "unskilled" positions at UPS. Those words are not in the Contract. Article 22 says if you are a "Preloader" or "Sorter" you get the extra dollar; "All Others" don't. It's up to each location to define how many jobs fall under the definition of Preloader and Sorter.
Also, some locations pay the extra dollar to additional people, and sometimes all people, if the location has a problem getting and keeping quality people.
Some managers may also pay additional people the extra dollar out of the kindness of their heart, or because they feel guilty paying near minimum wages to people who only work 3.5 hours a day and don't get benefits for quite a while despite the expense of paying union dues and initiation fees.
Article 22 clearly says the wage rates quoted are
minimums, meaning it's ok for UPS to pay someone an extra dollar (or more) if they want to.
In labor law there is the well established doctrine of
Past Practice which says if a favorable situation has been going on for some time and both the Union and Company know about it, and it doesn't violate the Contract, the Company can't just take it away unilaterally. UPS must negotiate with the Union first otherwise they commit an Unfair Labor Practice. It may also be an ULP to threaten to recoupe back wages in retaliation if a grievance is filed.
There is a "Maintainance of Standards" clause in my New England Supplement. Your Supplement might have one too. It says all working conditions, including wages, must be maintained at the high standard that existed at the time of the signing of the Contract.
I seriously doubt the payment of the extra dollar was a "mistake." UPS is probably just changing their policy as they look for more and more ways to dismantle the Contract and harm the business.
http://www.teamster.org/sites/teams...06 09 Final UPS Master Agreemnt 2008-2013.pdf
http://tdu.org/node/1617