March 2020 version incompatible with latest version

Hello,

Due to covid virus I've been working from home on the newest Power BI Desktop version (June 2020). Now back in the office from today I try to open my files but it says "the file is incompatible with the current version of PBI". 

How can it be that just 3 versions later (March vs June), the March version has already become incompatible??

I work in a big and sluggish organisation and from experience I know it can take months for a new update to be installed. So if this issue persists that would be a big problem for us.

Kind Regards,

Chris