The lifetime is a perpetual annual subscription. If the feature comes with the annual, it’ll be available to lifetimers.
Hypothetically, let’s say we added Dirac’s room correction, which would be an add-on cost to annual due to licensing (Dirac cost approx $500 in the past). That would not be included in the lifetime nor would it be in the annual. But if we built our own room correction and included it in the annual price, then it’d be available to lifetimers for no extra charge.
Note that the above is a hypothetical, and says nothing about future Dirac support. I only used it as an example since many of you are familiar with their product. Try to stay on topic here and leave Dirac support out of the conversation.