Oh dear, here we go...That's because it's EMS migrating to GMS, not the other way around. Had it been the other way around, we would have been expected to adjust to the EMS server time. Maybe it's b/c you're from EMS, or you're the one migrating, but if you look at it from the other side's perspective, the amount of complaints seen is completely justified.
If it had come to that, we EMSers would likely have been told to deal with it as it is. With that said, I feel that it's unfair for GMS to complain to this degree.