You sir, are on a very low level. If you believe delta is only parking that amount of 50 seat rjs, then I truly don't want my family on a plane with u flyin it.

Delta’s ALPA unit says it initiated the ratio concept.

The agreement lets Delta add 70 more 76-seat aircraft to its regional fleet, if it adds 88 mainline narrowbody aircraft and cuts its 50-seat fleet by more than 200 aircraft. But as Delta adds more 76-seat aircraft, the minimum ratio rises.

For example, when Delta adds its first 76-seat aircraft, the ratio starts out as a requirement for Delta to provide 1.1 block hours of flying for every hour of block flying outsourced to Delta Connection carriers. But the ratio increases for every 10 additional 76-seaters that Delta adds to Delta Connection service, ending at a mandate for 1.56 hours of mainline block hours for every hour at Delta Connection if the mainline operator adds at least 61 new 76-seaters to regional carrier operations. Once a new ratio is established, Delta cannot reduce it under most circumstances.

That guarantees mainline pilots at least 60.9% of the domestic block hours if Delta adds 61-70 of the 76-seaters, the Delta ALPA leadership says.