It's not exactly incompatibility. As with previous versions you can connect from 188.8.131.52 Viewer to 184.108.40.206 Host and update it if necessary (only now in beta the Simple update doesn't work yet, this is intentional - it will work in the final release).
Besides, there is another consideration - we just wanted to let as many customers as possible to upgrade for free. Given that this version has very important changes, namely new encryption algo and authorization scheme, we need as broad user base as possible to receive more feedback.
I didn't have this problem with the product that rhymes with Beam Screwer.
The Host was Current version: 220.127.116.11 whereas the Viewer was Version 18.104.22.168 Beta 1. As soon as I updated the Host to the most recent Beta version, it has stopped disconnecting me.
Yes, you should avoid version mismatch between Viewer and Host if possible. This is especially true about the latest beta - there have been a lot of improvements and a whole new authorization system implemented in it.
Still, we will see how we can better inform the user about version mismatch right in the program.
Thank you for your post. Please, make sure your phone and Host both synchronize their time from an online source, the option which is ubiquitous nowadays on all devices. Let us know if the problem persists.