Hello, I just want to congratulate you in your success and for making me cry with Charlotte in the 1st timeline's death(rarely do I encounter effective tear-jerkers these days). Before the Sky Fell was a great read, I couldn't put my phone down when I was still reading it. Having read it, it was wonderful. You gave a good representation of medieval culture, and I like the worldbuilding. In proportion to our own geography, I can see where the places would most likely be. And you also gave me a different plot, because I have a knack for predicting future fictional events but in this book, I couldn't. Although the climax was really tragic, it is very realistic. No new characters coming out of nowhere, no dead people getting resurrected and saving the day, none of that stuff. In short, I'm quite satisfied. There may have been some grammar and layout issues that need resolve, but it didn't really bother me(someone with OCD) because the plot was good. Though I am thirsty for a dramatic plot twist. But don't take it seriously unless you want to.
As I heard about the character genders issue, I don't really think you should since it wouldn't make since for me why Henderson did that or why Geoffrey did that if they were women, and medieval ages, as I see it, have a thing for feminism. So, in my opinion, no. Or any character, really. They're already perfect they way they are. You don't need to change it. I already love the story for it's full being.
And since I'm hooked, I am really awaiting the second book.