Hello Tomasz.
I am attaching a screenshot of my Publii uploading the blog. I didn’t commit any change, didn’t change anything. Just opened the application and hit the “Sync your website” button as I originally mentioned.

As you can see, Publii is uploading the whole website. This time it is showing “Uploading website (nnn of 479 operations done)” but If I publish new posts the number of operations will increase.
I mean: the whole website is being uploaded, no matter what I do.
Thank you very much.