We have a thread explaining the full timetable here.
Stimulus Checks Are On The Way -- Here's The Timetable
2) Social Security recipients get funds in their accounts between April 17th and 24th. Right after they do the bulk of direct deposits, the very next people who get stimulus money are those receiving Social Security, either through retirement or disability, including RRB. Your check will be direct deposited automatically, with no need to do anything.