MicroShift is not on a regular release schedule.
You may view the release page here
MicroShift is built from OKD, the Kubernetes distribution by the OpenShift community. The OKD version currently used to build is 4.8.0-0.okd-2021-10-10-030117
MicroShift is still early days and moving fast. Features are missing. Things break. But you can still help shape it, too.