It is not a good idea to close your month early due to Christmas.
Firstly: You may want to think about just paying out your owners prior to the 24th and then doing a month-end when you get back in January. (Just remember do not receipt any January-dated receipts until you have rolled the month of December over). There is no reason to close the month early as this will affect Owner Statements.
If you still decide to close off early: When you start month-end, make sure you change the date on the first screen (see image below). It needs to be changed to the date of the last receipts and reconciliation NOT today's date. Eg. if you receipted and reconciled to the 20th of Dec, but today is the 21st of December, you will date month-end the 20th of December. (So in the new year you can still date receipts for the 21st of December onwards).
Remember to allow for the banks being shut down, so do not pay out on the 24th as the client will not get the money until around the 30th.
When the pop-up appears for Owner Payments, double-check the date for these transactions as they should fall in line with your close-off date. (Do the same for any Creditor Payments, Ledger Payments and/or Agent payments).
Lastly, and most important of all, is the actual month-end close off-screen. Double-check that the close-off date is correct.
Once month-end has finished, make sure you change the Next Month End Date to the 31st of January.