Thanks for bringing your concern to our attention and for joining in on the thread, Tom99.

Yes, you cannot enter transactions with dates earlier than the Starting date of the inventory item you want to use. We can change the Starting value for you to be able to enter the transaction using the inventory item. Note that doing this will affect the initial value of your inventory. Here's how to do it:

1. Click Sales on the left menu and go to the Products and Services tab.
2. Look for the inventory item and click Edit.
3. In the Product/Service information window, click the Starting value hyperlink.
4. Click Got it! and it will route you to the Inventory Starting Value page.
5. Change the As of date and other inventory details if necessary.
6. Click Save and close.

You can use this article for reference when setting up an inventory item: Set up and track your inventory in QuickBooks Online.

After that, you can already enter the transaction you need to record.

You can always get back to us if you need additional assistance with your inventory. Have a great day!