I had been on ortho tricyclen for almost 20 years before TTC my son in 2013. First cycle off was about 31 days, then settled into 28-29 for three months, then bfp. I wrote a longer post if you search my old threads.
DS is 15 months now and we are hoping for another. Started back on the ortho tricyclen when I stopped BFing him at 11 months, took it for two cycles, and am now just finishing my first "real" period. It started 31 days after the first day of my last pill withdrawal bleed.