Date Conversion to UTC in Excel

I have the below dates received in an Excel cell. I want them to be subtracted from 8 hours from the given date

2022-03-16T23:02:14+08:00
2022-03-17T07:59:46+08:00
2022-03-17T08:00:34+08:00

Here, I need output as for Eg:

2022-03-16
2022-03-16
2022-03-17

>Solution :

Using helper columns to explain what happens:

• Column B returns the plain date
• Column C returns the time part
• Column D adds both values and subtracts the 8 hours (calculated as a decimal of 24 hours). INT is used to only return the date part – without time part.