Does he say the whole October is 'boy month' or he gave you fertile days that may or may not match your actual O days?
This is the same with Dr Jonas calendar, they give you fertile days each month and they give 98-99% gender accuracy IF you conceive baby on those days. You are not supposed to have sex but on those 3 days they gave you.
If your actual O date don't match their dates, and you decide to try on your actual 'fertile window', they can't guarantee your baby's gender.
See my point? It's accurate only on THEIR dates, so maybe you can try on your actual O dates and your swaying will prevale kwim? However, if their and your O date match, pregnancy is practically innevitable.
Here is the site of the Odan Institute
http://odan.jp/en/index.html , and they do the same thing. Gender calendar with your personal 3 fertile days (96% accuracy) is 24 euros and 99% which contains more detailed info is I think 77euros. It is basically your lunar fertility calendar based on Dr Jonas method.
Maybe, just for the piece of mind, you could order that 96% calendar and compare to your calendar?
HTH!!!! BTW, I'm obsessing like crazy about biorhytms :sigh: