The time periods shall be consecutive, have width equal to the
requested duration, and be aligned at the end of the requested time
period. This can result in a different size of the
first time period.
AlignmentEqualRounded
The time periods shall be consecutive, have width equal to the
requested duration, and be aligned at the alignment_time provided in
the request.
The alignment_time does not have to be inside the query period but
even if it is outside, only time periods are returned which overlap
with the query period.
A rounded alignment will typically result in a
different size of the first or the last time period.
