As of now, they are not sure about any sign-ups ( not needed ) and they are waiting for more instructions from government
check this site for official updates
https://www.irs.gov/coronavirus
WHO ARE ELIGIBLE ?
Economic Impact Payments: What you need to know
The distribution of economic impact payments will begin in the next three weeks and will be distributed automatically, with no action required for most people. Social Security beneficiaries who are not typica