I'm a newbie - so go easy please...I did search for this question.

If a ship would end its move with its base physically overlapping another ship and part of its base outside the play area, what is the effect?

(for both victory conditions of some missions and fleeing the battlefield)?

1) Is it "immediately destroyed (or meet the victory conditions)"?

2) Moved back along the movement template in contact with the overlapped ship?

(Can I move a ship into position to block another ship from leaving the battlefield?)

Same procedure for any other overlapping situation.

Move the ship back along the template until it is no longer overlapping - if any part of the base is outside the play are AFTER doing this, the ship is removed from play.

and yes - you can block a ship from leaving the play area - but only if it's final position would overlap the blocking ship - if it passes through the blocking ship without the final position of the base overlapping it can still leave

I'm always amused when someone starts a post with "I'm new at this game, so please go easy on me..."

We're not a sarcastically harsh bunch here, are we?