I attached an image which shows a Costco transaction with the date 12/30/2023. When the link to the google spreadsheet was added to Fina (as a manual account), the date of the transaction shown in Fina was behind by one day.
I random picked a couple of transactions throughout the year and compared what I saw in FINA vs what was in the googlesheet containing the transactions. The date in FINA was always behind by one day.