A Lander (non fearless) on the ground pics up enough blast markers to break it.
It cannot move and so cannot move beyond 15 cm of the enemy and so is destroyed.
However in this instance there is no enemy with 15cm

Is it still destroyed?

Or does it convert it's broken status back to blast markers if it survives the round and takes off?

No.


Yes.

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Currently doing a plastic scenery kickstarter

Ben has it correct.

No

Yes.

Also note that it still takes damage for BM's when shot at after being broken, as with normal War Engines.