We seem to be making a very simple formula quite complicated.
1) ~150-350 Pilots will remain at ENY by passing on the flow.
2) Protected Pilots Flow at 50% of AA Classes meter-able to 25 per month. (~725 Pilots)
3) PP to DOS Group is 35% of AA Classes meter-able to 15 per month. (~150 Pilots)
4) The last group is 25% of AA Classes PER YEAR meter-able to 5+((seniority list - 480)/125)*12 or roughly 180 pilots per year with a pilot group of 2300. (~1300 Pilots)

BTW... Group 4 in this case is the supporting evidence for an increased flow rate with an increasing pilot group size. It makes no difference for the PP and DOS guys, but the last group has an increased interest in a growing pilot group.

A Pilot hired today is realistically (Assuming Metering and 11 months of flow per year, minus 10% per year attrition/retirement) looking at...
Group 1: Adds 0 (Flow) Months (Retirement/Attrition Does not matter here)
Group 2: Adds 20 (Flow) Months (Retirement/Attrition- Roughly 75 per year)
Group 3: Adds 9 (Flow) Months (Retirement/Attrition- Roughly 10 per Year)
Group 4: Adds 5.5 YEARS!!! (Retirement/Attrition- Roughly 107 per year)

The Grand Total... 8.5 Years to flow!!!

If you joined Envoy purely for the flow, those are the numbers with some big assumptions in there. If you joined for any other reason (commutability, pay, benefits, etc) then quit worrying about the flow and start worrying about you pay/benefits over the next 8.5 years.

8.5 years of pay at our current rates versus 8.5 years of pay at the rate negotiated by EDV is worth far more than having some flow date that may or may not move. Your flow will come, now lets focus on reserve rules, compensation rates, integration of bonuses into pay rates, and things that will actually matter over the next 8.5 years. Our reserve system sucks, and yet we spend all of our time and effort talking about flow. Focus on the things that matter.