Clarification regarding ERA5-Land data

Dear Colleagues,

I hope this brief contact finds you well.
While working with ERA5-land data (temperature, radiation, wind and pressure data), I have come across a little misunderstanding, which I hope you could kindly answer.
Suppose I have a data for 2-m dew point temperature of 280 K for 2023-06-16 00:00 UTC. This value represents which time window: 2023-06-15 23:00 UTC to 2023-06-16 23:59 UTC or 2023-06-16 00:00 UTC to 2023-06-16 00:59 UTC? Does this change for the other variables?

Best regards,

Arthur Boari