The thumbnail CG is the new title screen for PC/Linux/Mac, Android on the other hand gets a different one because apparently no one knows to swipe down to hide text box.
About Sierra backstory, there definitely will be more about her next version.
Geez, is it such a big deal? https://mega.nz/file/VytnhYrB#KMOPUlDm54rN8I-Ss7Lqm85ucF3EWoj8NeZbRy-pP1g
I repacked it with the new title screen.