Pre ES 2.x, I use the Date Histogram Aggregation and in particular the time zone related fields (pre_zone/post_zone), to aggregate data and return in the correct time zones.
I understand that in ES2.x, time_zone fully replaces pre_zone. However, the post_zone function has been completely dropped. This was rather valuable as I was able to give ES a timezone, and it would return the data bucketed in the correct time AND return the timestamp key for the BEGINNING of the interval. Now, it seems that there isn't a way to replicate post_zone without bringing all the date keys into the application and doing the date offset and rounding based on the interval.
Am I missing something? Is the post_zone function still producible in some manner? This almost seems like a regression in function to me...