Welcome @fizza,
You may (often) use the search function of this forum to find an answer, e.g. What are the relation between these columns you get while exporting data in Excel?.
Hints on international standard timezones can be found here: https://www.utctime.net/ and
ISO 8601 - Wikipedia.
For a deeper discussion concerning KoBoToolbox see Multiple submissions randomly appeared all at once on server days to weeks after submitting - #11 by jnm.
