I need you to clarify this sentence.

"With the discontinuation in 2023, you can still use the app if you have purchased a not subscription-based".

I have Quickbooks Desktop 2021 which as far as I could establish is only available on a subscription basis, without a subscription one cannot log on.  Does this mean that on 1st February 2023 I can no longer use QB desktop?

It's important that Intuit clarify this to avoid mis-leading many of its Desktop users who think they can continue using QB Desktop unsupported.

If QB Desktop 2021 is available for purchase for a flat fee, then I would appreciate being told where I can get it.  I tried to locate a for purchase version last year but couldn't find one available anywhere.

When it comes to QB Online, Intuit has consistently failed to address the reality that there are many companies in existence that exist for specific limited purposes with small volumes of transactions.  It continues to only offer a one size fits all subscription for every company regardless of size or volume of activity.