I picked my first snow peas today. According to the calendar I'm keeping, it took 10 weeks from the date I planted the seeds to the date of my first harvest. That's 70 days when planted in August. The seed packet says 60 days to maturity/bloom. I suppose that's about right, since they started flowering a couple weeks ago.
I just saw the first bloom on my English peas yesterday. Those were planted from seed at the end of September, so it took 7 weeks for them to bloom. I'm guessing it will be another 2-3 weeks before they have fruit big enough for picking.
So the moral of the pea story is that it's about 10 weeks from seed start to harvest when I plant in the fall. I intend to keep succession planting and see if that's the norm year-round.