If you got your PDF of 1.1 through itch you should be able to just download the updated file from here. If you got your PDF as part of buying a physical copy from elsewhere, let me know and I'll get you a proper itch.io key so you can download an up-to-date copy :)
If you got it through the Kickstarter and downloaded it before with this account, you should be able to download it again to get the new version :) If you haven't downloaded it before: I sent all Legacy backers a download key after the campaign was done, so you should have an email from itch.io with the key (from March 2023). I hope this helps, otherwise let me know! :)