How many years since rescue??

I am relatively new to Lost. I've been watching Season 5 since the beginning and I've watched Season 1.

They mentioned that it has been three years since Kate/Jack/Sun/Syid/Hugo have been rescued.

Does that mean that the people left on the island: Locke/Sawyer/Juliet also have been there for three years jumping through time?

And if so, how does it explain that Jin turned up only now? Are they trying to say that he was laying on that raft since explosion for 3 years?

If someone could explain this time difference, I would really appreciate it!!!!

Also on Fandom

Random Wiki