Can I Receive Another Covid Extension After My Initial 20 Days?

Covid Extension Part 2

I've already been granted an 'under consideration' 20 days Covid extension stamp.

My question:

When I return can I get another 20 days under consideration stamp?

If not:

Will I get 30 days extra added on from my initial Covid-19 visa extension?

OR:

Will the 20 days I've already been granted be deducted and they'll add on 10 more? (Total 30)

Thanks