We have an AW here that went from Navy Helos, straight to Spirit fly A320 via ATP AMEL in a piston twin - no Regionals required. No prior airplane category time other than SNA VT's...Eh, dropping currency at the boat sucks but you can get back quick if you want. I was at a regional less than a year before starting at the majors. I wouldn't be shocked if things continue the way they are, regionals won't even be needed and they'll take you non-current in that 12-24 month range. It's the "haven't flown in 10 years while riding a desk" folks that can have issues spooling back up.