as this has been issue on GW 2012 and was supposed to be fixed with sp1 (765954 Calendar Publisher - All day appt showing up 1 day early on weekly and daily view) i'm quite disappointed that this issue came back in GW 2014.

when you subscribe to a new calendar which holds all day appt those appt show up 1 day early on monthly, weekly and daily view (mutli client)

can so check this.