Statistics for COVID-19

As someone familiar with databases, I have been wondering how deaths have been recorded.

I have always assumed that date and cause of death were on the death certificate and this information is recorded. I also understand that all deaths are recorded by the General Register Office in Southport for England & Wales (similar organisations in Scotland & NI).

What kind of database are these organisations using that cannot be queried for deaths caused by COVID-19 on every date. This excuse that data is not processed at weekends is just hogwash as the date of death is recorded.

Does the Office of National Statistics not have direct access to the General Register Office data?