The screenshot gosa posted, as I would interpret it, says: No major updates in the form of perpetual versions, starting with a version that has yet to be disclosed by Topaz. The only correct way in terms of customer service and appreciation would be to roll out the new version that dies after its subscription runs out not earlier than in a year, when the subscriptions to owned versions have all run out. With this, there would have to be a halt by Topaz on all new subscriptions to owned products as well as extensions of existing ones. But I second what gosa wrote, the pay-or-trash-it model may start with 8.5 and anyone that has subscribed or extended during the last couple of days will not get what was paid for, which is a post-8.4.2-version that is permanently owned.
BTW, a subscription model will likely require online validation of existing subscription any time GPAI fires up. The commodity of using GPAI in an offline environment will probably be gone by then.
BTW2: Never got the e-mail about the new subscription model. No, it is not in my SPAM folders, either.