A date as epoch ms. A date on its own ('YYYY-MM-DD') means midnight UTC —
the same moment wherever it is checked — and must be a real calendar
date; anything else is an ISO 8601 moment, which must carry its offset
('Z' or '+02:00'), or it would mean a different moment on every device.
A date as epoch ms. A date on its own ('YYYY-MM-DD') means midnight UTC — the same moment wherever it is checked — and must be a real calendar date; anything else is an ISO 8601 moment, which must carry its offset ('Z' or '+02:00'), or it would mean a different moment on every device.