Update according to latest test results: (see newest screenshots for visuals)
End Crystals and Primed TNT exploding at coordinates higher than 8388607 (any direction, for instance: x=8388608, z=8388608) have an offset in their destruction area (they explode the wrong blocks).
2016-10-06_17.37.17.png show the "default" explosion, 2016-10-06_17.37.25.png shows displaced primed tnt (MC-92901) and the other image shows the explosion damage from the last image.
video
Edit: There is no damage in the opposite under region (see 7th/8th image)
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You can update the affected versions yourself.

This ticket actually duplicates MC-92901, as the explosion comes from the position of the entity, which is offset. And this offset is not visual: if you use any of the next commands, an armor stand will be summoned at the exact position of the specified entity.
/execute @e[type=tnt,c=1] ~ ~ ~ summon armor_stand
/execute @e[type=ender_crystal,c=1] ~ ~ ~ summon armor_stand
Can confirm for 16w02a