Hi, Is there a way to change the displayed information to the financial year, ie 5th April 2019 to 4th April 2020?

Yes, there is, @ian-gregory5.

You'll want to customise your financial reports to show the preferred date and data you need. I'd be glad to guide you how.

In your QuickBooks Online (QBO) account:

1. Go to the Reports menu.
2. Select your Financial Activities report.
3. Adjust the date of your report in the date field.
4. Once done, click Run report. 

Here's an article you can read for more information on generating a report: Customise reports in QuickBooks Online

Also, you'll want to check this article for the detailed information on how to save the current customisation settings of your report:  Memorise reports in QuickBooks Online

Let me know if there's anything else you need help with. I'm more than happy to work with you. Have a great day and keep safe.