In case you're not getting the emails, they are posting these as Update messages on the Kickstarter page for the book.
In some ways Im not surprised, as supply chain issues have been an ongoing thing for them, including the fiasco of getting the original arts framed (which was eventually discarded entirely in favor of the custom slipcase).
Eagerly awaiting this book, I admit Im a little frustrated with the delays. I guess it's better they get everything right and take their time, but still...I have to think many people backing this and paying as far back as Dec 1, are going to start wondering where the book is.
The extra goodies they are adding are nice...hopefully it doesnt become too complicated...Im already seeing like 8 different 1/1 colored bronze, multiple other characters than the Spiderman, true-card colored bronze, and possibly this new variation, unless Im reading that wrong. I cant be upset with more goodies though