The PS5, Series X and PC next gen upgrade patch for The Witcher 3 has been delayed again. In an official statement CD Projekt Red says the patch has been delayed "until further notice". So it's pretty much delayed indefinitely. Here is the official statement from the official Witcher twitter account.
"We have decided to have our in-house development team conduct the remaining work on the next-gen version of The Witcher 3: Wild Hunt. We are currently evaluating the scope of work to be done and thus have to postpone Q2 release until further notice. We'll update you as soon as we can. Thank you for your understanding."