The correct behaviour would be to actually use the timezone field of an ISO date and not to assume that convertion to/from utc is always lossless. A single num

The correct behaviour would be to actually use the timezone field of an ISO date and not to assume that convertion to/from utc is always lossless. A single number is not enough to store a datetime. I blame databases for only storing half of the data and leaving the other half to the environment.