@mamuang
Last year my pear ripening time was off due to the drought and heat. Last year my Duchess D’ Angoulme ripened in September but everything was off a month. Sometimes the Duchess ripen in October or November for me. Here is my personal log of what happened and i kept pretty good track in this post i think Here comes the 2018 apple & pear harvest!
I would compare my ripening times to this list from grandpas orchard and that should be a close list GOWeb-MaturityChart-PEAR(2013).pdf (110.8 KB)
Last year my pears were at least a month early and i know that from all the literature i read. The list below from Grandpas is accurate on September pears (around Sept 1-7) but mine ripened in August. The pears on the list below I will log the dates of again this year on a more normal year
Harrow Sweet™
Karl’s Favorite aka ewart
Magness
Potomac
You can also cross reference with this list Here comes the 2016 apple and Pear harvest! but keep in mind Kansas usually cooks everything ripe in July and August once the 100 degree temperatures hit.