Apple are expected to announce the availability of MacOS 11, Big Sur, shortly. Unfortunately this sees a change to kernel module loading that will stop the existing AuriStor AFS kernel modules loading and so AuriStor client version 0.198 (and earlier) will no longer work.
If you require AFS your your Mac, we don’t recommend upgrading to MacOS 11 until AuriStor announce a compatible version of their AFS Client.
Update: In January 2021 Auristor published a blog article on how to install their updated client on to Big Sur (11.0). It is somewhat complicated by the increased security measures in Big Sur, particularly on Macs based on Apple ARM-based processors.