Paying for Nothing. Unsolved Problems for free.
There is a known Issue that Birthdays synced with Exchange (90% of professional users) are shown correctly in the calendar.app on iOS devices, but one day too late on calendar.app on MacOS.
User Mathieu_ and Barney-15E discussed it here some time ago, and gave also the correct answer: there is no solution to the problem, and nobody, at Microsoft and at Apple (!!!), is interested to solve this ridicolous BUG.
They make billions of profit with our licences, but they are not able to provide software and OS Solutions that are able to display birthdays on the same day on different devices.
The answers form Apple Support, that one should try to sync over iCloud are simply ridicoulous.
Please don't answer if you don't have a solution. Thanks.
iMac Pro