It is absolutely unacceptable to short time that was worked. Ask your sup for a PDM (payroll datamart) history. Most of them have the ability to pull these up themselves and do not have to wait for the payroll department to send it to them. It can be exported as an Excel file. It will show each day, start time, end time, work activity, rate paid, hours worked, etc. It will be in hundredths of an hour, not minutes. This is different from a payroll history that shows your total wages and taxes.
I would like to believe that no one is intentionally taking paid time away from employees. However, I have seen plenty of Time and Labor adjustments submitted by operators who do not understand the difference between minutes and hundredths. Example: for some reason you have no timecard for Monday and an adjustment is submitted to payroll. Adjustment are supposed to be submitted in hundredths. Let's say you worked from 5:15am - 10:45am. This should be entered as 0525 - 1075 and you would be paid for 5.50 hours. If the operator enters the adjustment as 0515 to 1045, you would be paid for 5.30 hours and would be short 0.2 hours. Payroll has to enter the times as they are submitted on the adjustment and can not try to guess if the person meant minutes or hundredths.
I don't know what the timecards look like at the centers but all of this information can definitely be obtained via PDM or asking payroll for the detail.