How does this change the way I use invoices and other legal documents?

There should be no changes to how you use invoices and other legal documents. As a sole trader, your personal name is already included by default in your Tide invoices alongside your trading name. If you’re using another invoice platform or tool, we would strongly advise adding the personal name registered to your account next to your banking details. Your Tide statements currently only show your trading name, but this will change shortly. This will be more useful for you when showing proof of earnings or applying for credit than just having your trading name.