I invoice today for services that will be delivered in the next few weeks. If I use revenue recognition and enter an estimated service date, can I change it before EOM?

Glad to have you here in the Community, @bburkeen

Let me share some information about using revenue recognition and entering an estimated service date in QuickBooks Online, to change the invoice service before the end of the month.

Indeed, it is possible to make changes to revenue recognition, such as invoices, as long as it is done in the same month as the original service date. Otherwise, it is not recommended as the schedule has already started and errors may occur. It is best to make any necessary changes before the end of the month or the revenue recognition schedule. 

You can follow the steps below on how to edit:

1. From the Sales tab on the left panel, choose Invoices.
2. Look for the Revenue Recognition invoices. Click the Edit icon or tap the dropdown tab, and select View/Edit.
3. Update the invoice. Once done, click Save.

Additionally, feel free to visit or save these articles in case you will need them in setting up an automatic schedule to help with revenue recognition in QuickBooks Online Advanced: Set up a revenue recognition schedule in QuickBooks Online Advanced

Please keep me posted if you need more assistance with handling your invoices in QuickBooks Online. Have a pleasant day and Keep Safe!