I went and looked at the chart and then went back to the page you linked to in order to read and see if he mentioned row 55. He did, and this is what he said:
I worked through row 55 of my chart (highlighted in Orange) before working the edging bind-off. I have included additional feather-and-fan repeats beyond where I concluded mine for those of you who would like to work a larger blanket.
So he stopped his at row 55 but if you want to go further the chart extends more for that.