So I've talked to a steward about this and he seems to think I just got "lucky".
I got a 50 cent progression raise after August 1st($9.50 to $10.00). So my retro pay should technically be 70 cents from August 1st to my one year seniority date, then 50 cents from that point on(bringing me up to match the new higher starting wage progression schedule, $10.50 at 1 year).
However, the retro check paid me at 70 cents for all hours worked August 1st- April 25th. I know my math isn't wrong because it's pretty simple, divide total pay by total hours listed, comes out to .70 for straight hours.
So should I view this as a payroll mistake, and feel lucky? Or should I use it as proof that I should get my post August 1st progression increase AND the 70 cent General Wage Increase? (which would put me at $10.70 not $10.50)