It does not provide support for adjusting dates based on time zone data - this is provided by the Moment Time Zone library.For an in depth description of this issue, see the Stack Overflow tag.
This means that 1.5 rounds to 2, and -1.5 rounds to -2.
Frequently, people are confused about the difference between time zones and UTC offsets.
In a later release, the parser will default to using strict mode.
Strict mode requires the input to the moment to exactly match the specified format, including separators.
Arithmetic is another area where the native Date object is lacking. This section lays out some guidelines about how to correctly use the parser in your situation.