If retire at 50 , 2.5 M cash, debt free, 5% return 10Kpm
If retire at 55 , 2 M Cash , debt Free, 5% return 8Kpm
If Retire at 60 , 1 M cash, debt free , 5% return 4Kpm supplement by decreasing the 1 M
base money. ( assuming 25years = additional 3.3K pM)
Balance cash for future generation

The longer I hold off retirement, the less I need...