Hello, I’ve been searching the forum for something related to this date problem. I’ve been experiencing a similar problem, but in my case it’s using any formulas. Both my Handsontable and Hyperformula instances are configured in the same locale, but even using the default, all the functions return a day earlier than they should be. In the example I use a specific date and define a date function in another cell, to add a month to the cell in relation to the original date, but instead of returning the same day of the next month, it returns the previous day.
Handsontable date problem exemple - JSFiddle - Code Playground
note that for correction, in the first EDATE function I added a day to the function’s return.