LSAT-Flex will be made up of genuine LSAT test questions. The format will be identical to that of the Free LSAT Prep practice tests found on LSAC’s LawHub, but LSAT-Flex will be composed of three 35-minute scored sections instead of the traditional four scored sections and one unscored section—seemingly a big advantage for test-takers for whom endurance is a challenge.. LSAT Writing will continue to be administered separately.
LSAT-Flex will be available on any laptop or desktop computer with a Windows or Mac operating system. You’ll be monitored by a live proctor through webcam and microphone while you test. Learn more.

Yes. All test-takers who received accommodations approval for the traditional LSAT will receive the same or equivalent accommodations on LSAT-Flex.

The short answer is, no.
There will simply be one scored section of Logical Reasoning, instead of two. LSAC has assured test-takers that the LR section will operate typically in terms of length and level of difficulty.

Mathematically speaking, yes.
As most LSAT preppers know, Logical Reasoning usually counts for 50% of your total score, with Reading Comprehension and Logic Games clocking in at 27% and 23%, respectively. Under this new schematic, the balance of power shifts quite dramatically. We can assume LG will have 23 questions, LR likely 25 (or 26), and RC 27. With that configuration, that means Reading Comprehension now counts most – representing 36% of your scaled score. Logical Reasoning and Logic Games will now account for 33% and 31% of your scaled score, respectfully. That should result in a shift in your preparation priority.

While this has not been released by LSAC, we took our best shot. To quote our outstanding statisticians on the methodology: 
We took an average of the minimum number of correct answers needed for a certain score in the last 3 years, and then multiplied that by 75/100.78 … i.e., [75 expected Qs on LSAT Flex (23 LG + 27 RC + 25 LR) / 100.78 (the average # of Qs per PrepTest the last 3 years)]. Then, we rounded those figures to their nearest integer and started assigning numbers from 180 down. If a number was already used, then that scaled score was unscorable.
While this cannot be used to perfectly calculate your score yet—as the official scale has not been released—by adding up the number of correct answers of your Logic Games, Reading Comprehension and average Logical Reasoning performance on a given PrepTest, you should expect a score similar to what you’ll see in the table we’ve put together.