unadvised changes

[twobags]

Hard one to describe really but here goes ................the other day i noticed that the timings on the two duties on our park and loop duty were different finish times usually by 1/2 hour , These timings were the same until recently, but then yesterday i noticed my own timings had been changed slightly the duty prep times increased each day by 35/40 mins .monday finish increased by 25 min the rest shortened by 5 or 10 mins ,so with all changes made prep has risen delivery time shortened which dont make sense ,also when i asked no one had an answer except the crap ex rep [ quit as rep dec 31] he said that that would probably be prep time on return, can they make these changes with out consult to union or myself, spoke to area rep who said he knew nothing about it [he now covers our office .