I too have found QuickBooks Online Advanced purely by chance. Astonishing, considering our commenting and complaining that there was no viable replacement for Desktop Professional/Accountant. There was nothing relating to this as recently as the end of March. I have been a QuickBooks Advisor for 20 years yet not a single indication about this software or that it was even being developed. Advanced is the answer to our concerns, it does part deliveries of purchases without having to re-input the remaining order - something Online did not do. It has projects that link to the customer and costs for purchases. It allows time to be input to the project without needing payroll. Expenses are an actual thing! I have a client who went to Sage in April and is now transferring to Advanced. I have renewed faith in QuickBooks but not Intuit or it's management. If they have been listening to us why not launch this product with fanfare? 

With regard to Desktop after 30.06.23 I believe although absolutely no one has confirmed this, the extraction tool will not have a cost. But do be warned I understand you cannot get copies of your sales invoices, all you get are limited reports - no choice - and it is for 7 years only. Not the read only access at a one off licence cost that we were originally promised.