I'm having the same problem. I reserved for Sunday at 8pm but my girlfriend's blank invitation says 9pm. Since we are advancing the clock on Sunday morning at 2am it seems like her invitation is taking into account daylight saving while mine doesn't. When she check the reservation npc for Sunday, the available time slots are 3am/5am/7am etc..while mines are 2am/4am/6am etc... She's on PC and I'm on PS4, we both check our systems clock and we are in the same timezone (we live together).