And why you may need to repeat AT TIME ZONE 'UTC' twice. SUMMARY * AT TIME ZONE 'UTC' converts the data type from timestamptz to timestamp (example). * Now you are inadvertently using the timestamp without time zone (aka timestamp) data type, which is markedly discouraged. * There are tons of footguns with timestamp. * For example, the equality of timestamp and timestamptz will always be false. * Adding a month with + INTERVAL '1 months' is timezone-dependent. If your product