It's likely to stay true. The creators know that fans have expectations based on the original, so they'll do their best to preserve the essence. Maybe there'll be some new twists and developments, but the fundamental storylines and characters should remain recognizable.
I think it will. Usually, sequels try to maintain the core elements and spirit of the original to keep fans engaged.
Most probably yes. To keep the success going, the story continuation is likely to build upon the original's foundation while adding fresh elements. But the core of the world and the characters' traits are expected to be intact.