Good morning, @PBMB.
Welcome to the Community. Thanks for chiming in on this thread as well.
At this time, you won't be able to switch to the new experience once you're back on the old one. However, there's a workaround that you can use to access the new invoices and estimates. Follow these links each time you want to create one using the new format:
Also, send feedback to our Product Developers if you'd like the new experience to come back permanently.
This should answer your question. Feel free to come back if you have any other concerns. Happy Thursday!
