your supervisor has the right to make the regular fix the case labels... talk to your steward and show them this.
M-38 MANAGEMENT OF RURAL DELIVERY SERVICES
343 LABELING
343.1 General
The postmaster or designee
must assure that all cases in the unit are labeled
efficiently and uniformly
Methods Handbook, Series M-38http://www.apwu.org/dept/ind-rel/USPS_hbks/M-Series/M-38%20Management%20of%20Rural%20Delivery%20Services%207-80%20(243%20KB).pdf
There is nothing so powerful as truth, and often nothing so strange.