The Digital SAT is not one fixed set of questions handed to every student. Both Math and Reading & Writing are split into two modules each, and the second module you get is chosen based on how you did on the first. This is what "adaptive" means on the Digital SAT -- it is a two-stage design, not a question-by-question adjustment.
Module 1 of each section (Math and Reading & Writing) contains a mix of easy, medium, and hard questions -- every student who starts a section sees the same Module 1 difficulty mix. Your performance on Module 1 then determines which version of Module 2 you route into: a version weighted toward harder questions, or a version weighted toward easier ones.
This means two students who both finish Module 1 can end up taking meaningfully different tests in Module 2 -- different questions, at a different difficulty level, calibrated to what each of them has already shown they can do.
Routing into the harder Module 2 is not a penalty and routing into the easier one is not automatically bad news -- it is how the test narrows in on your actual ability level efficiently, in a fixed number of questions, instead of asking everyone the same broad difficulty spread. That said, the harder Module 2 has a higher score ceiling: a strong Module 1 performance is what unlocks the chance at the top of the score range in that section.
This is also why "practicing on a fixed-difficulty quiz" only gets a student so far. A test bank that does not route students the way the real Digital SAT does cannot give an accurate read on where a student would actually land -- which is the reason Satestify's adaptive practice and full simulations use the same two-stage routing logic (Module 1 mixed, Module 2 branches on performance) rather than a static question set.
Treat Module 1 of each section as the part that decides your ceiling, not just "the first half." A rushed or careless Module 1 caps what Module 2 can even offer you, regardless of how well you'd do on harder questions if you saw them.
Practicing under the same adaptive routing you'll face on test day -- rather than a fixed-difficulty problem set -- is the only way to get an accurate sense of which Module 2 you would actually route into, and therefore what your real predicted score looks like.