From this Friday the beta Stage 2 client will be avialable to download from PSN store which will - most likely, unless some major "overhaul" would be needed - become live one as well with some minor patches to be downloaded prior the start of early access at 11 April. Even if SE would decide to release the new client for live (which I doubt) it's quite likely that it will be "freely" available on PSN without need for codes as well as it's practically useless to anyone without active / paid for service account anyway. Although Sony might force SE to "protect" the download with PSN voucher code at which case I'd assume it would be retrievable via Mogstation during the Migration / upgrade process.