My IRS.Gov says my check is scheduled to be mailed out by March 6 which is 2day.It wasn't mailed b/c the bar is still on refund approved.Does any1 knw how long it takes?

I am just super confused as to why it says it should be mailed out on the 6th of March and it wasn't.? How long before they actually mail it out?  It also says if I don't recieve it by April 3rd then I need to call.   That's a long waiting period.