I was playing with CFIREsim and FIRECalc. It seems that due to our dual pensions and highish social security, we are getting a 100% success rate using a 6.67% withdrawal rate (annual spending about 2.5x our actual minimum expenses and pensions, which kick in 12 years after retirement, cover more than our minimum expenses).
I had been considering that something like this might be the case instead of using a 4% withdrawal rate, when we hit our pensions our withdrawal rate goes so low, that I suspected we could have a high initial draw rate. Target retirement ages: 50 (which isn't too far off). I was originally thinking age 52 is when we would hit our target, but now 50 is very realistic. Additionally, with such high annual spending it will be easy to back off if the plan is not going as expected.
Gotta love that pension!