After installing the October 2024 Cumulative Update (or any subsequent update) for SharePoint Server Subscription Edition, the Date column values in lists may incorrectly display as December 30th, 1899, instead of the correct date, under the following conditions:
- The site locale uses a date format where the day precedes the month (e.g., DD.MM.YYYY or DD/MM/YYYY).
- The day value of the date is greater than 12 (e.g., December 14th, 2024).
- The list contains at least one column with custom formatting enabled using JSON (this column does not need to be the Date column)
February 2025 CU for SharePoint Server Subscription Edition includes a fix for this issue: