Josh Good mentioned this on LinkedIn a little while ago, and Bruno Calver mentioned it on a UK Qlik Meetup earlier in the week.
It will mean that you can carry on using Qlik Sense Desktop after the end of the month, and that pesky start-up message will go away.
I think that you need to get the June 2020 release of Desktop to make it work. I've tried it with the Feb release and it kinda works, but not quite. It requires you to log in each time, where when I have authenticated against a client-managed Enterprise server there is no pop-up at all when opening Desktop.