First, I do not know for sure and Jim is right to ask PG Music directly. I first thought the same as he did, to ask whether you had an upgrade license or a 'full' new license for BIAB 2023. It does sound like you should at least call PG Music Sales and give it a try to negotiate something. You have nothing to lose.

I read that thread as well, about buying only the Pro version for your Mac and then converting the format of all the audio files. I guess it boils down to the value of your time to go through that conversion.

I assume you would have to deactivate all three licenses of your existing Windows installation to get any hope of transferring it to another user.

Let us know what you decide.

ps it's good you asked this question publicly. There must be others wanting to transfer platforms and the cross grade pricing might be prohibitive for some.

BIAB 2024 Win Audiophile. Software: Studio One 6.5 Pro, Swam horns, Acoustica-7, Notion 6; Win 11 Home. Hardware: Intel i9, 32 Gb; Roland Integra-7, Presonus Studio 192, Presonus Faderport 8, Royer 121, Adam Sub8 & Neumann 120 monitors