Any way to check previously installed version?

You can run this query in Database Manager to see all the updates you have done.

Select * from ConfigWizardLog where module = 'Orion Core Services'

Very Helpful.  Is the HF version part of the Orion Core Services version number?

I upgraded a week ago to 2020.2 HF1 as well as yesterday to HF2 and both are 2020.2.15300.12766.

Thanks!

You would be impacted as you are not running HF2 on that version. HF2 addresses the largest compromised parts.

Out of curiosity why do you want to check the previous version you had installed prior to HF1? 

I wanted to see if you were able to find a query that shows when the hot fixes were installed? I'm getting requests for this and I can only provide them the same information as you. 

Thanks,

Alex