Due to multiple questions we want to clarify the licensing scheme of bcAdmin4
Runtime: bcAdmin4 licenses allow updates and free standard support for a certain runtime. This is always based on the calendar year. So with a license for 2020 you are able to use all updates published within 2020. From 2021 on you can’t use the newer updates without a license update. You can get a license for multiple years in advance, thus for example all updates until 2023.
Multiple licenses: If you have multiple Macs and thus multiple licenses, these all need to be the same license year. Thus you can’t have two Macs licensed only until 2019 and one until 2020. This is technically not possible and not intended.