Dates in SharePoint list changing with Regional settings change

On changing the regional settings of the site, the dates jump forward/backward in columns within the list. This can’t be right. Because, if the list is of birthdays of employees (say 1/1/2000) and if we change the regional settings from UTC to London, Lisbon, Dublin time, the birthday changes to 2/1/2000

FYI, I am on SharePoint Online 2013

Any advice appreciated

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