When I set up a recurring journal, for example depreciation charges for say next 12 months.. There is a box 'Create xx days in advance, what is its function?

Let me explain to you what the Day in advance option is for, ken-pratt1.

This gives you visibility into future cash flow as well as the ability to send reminders to clients before the transaction date. You can enter the value for this field when editing the schedule of a recurring template.

To make things clear, if your transactions are scheduled on the 15th of every month, but you want to send customers a reminder 10 days in advance, enter 10 in Days in advance to create. QuickBooks Online will create transactions on the 5th of the month. On the 5th, you can print invoices and send reminders, but the transaction date remains on the 15th.

You can run and print reports in QuickBooks Online to get the information you need and to be able to secure a file. 

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