According to this new digital registration process, new companies that wish to file H1B petitions for 2021, need to register online.
This will make the current H1B registration processes for companies easier and streamlined.
Under this new process, employers seeking H-1B workers subject to the cap, or their authorized representatives, will complete a registration process that requires only basic information about their company and each requested worker.USCIS
This process shall be initiated from March 1 through March 20, 2020.
It appears as though this is a filtration process whereby the Govt. can scan companies and choose the ones that are eligible for H1B processing.
Source – USCIS Press Release