Program: 34024
Project: 34024
Buggy source:
/** 
 * Ensures that any block when loaded will match the biome of the center column of the island if it exists. Does not apply to spawn.
 * @param e
 */
@EventHandler(priority=EventPriority.LOWEST,ignoreCancelled=false) public void onChunkLoad(ChunkLoadEvent e){
  if (e.getWorld() != ASkyBlock.getIslandWorld()) {
    return;
  }
  for (int x=0; x < 16; x++) {
    for (int z=0; z < 16; z++) {
      Island island=plugin.getGrid().getIslandAt(e.getChunk().getX() * 16 + x,e.getChunk().getZ() * 16 + z);
      if (island != null && !island.isSpawn()) {
        Biome biome=island.getBiome();
        Biome blockBiome=e.getChunk().getBlock(x,0,z).getBiome();
        if (!biome.equals(blockBiome)) {
          e.getChunk().getBlock(x,0,z).setBiome(biome);
switch (biome) {
case MESA:
case MESA_BRYCE:
case DESERT:
case JUNGLE:
case SAVANNA:
case SAVANNA_MOUNTAINS:
case SAVANNA_PLATEAU:
case SAVANNA_PLATEAU_MOUNTAINS:
case SWAMPLAND:
            boolean topBlockFound=false;
          for (int y=e.getWorld().getMaxHeight(); y >= Settings.sea_level; y--) {
            Block b=e.getChunk().getBlock(x,y,z);
            if (!b.getType().equals(Material.AIR)) {
              topBlockFound=true;
            }
            if (topBlockFound) {
              if (b.getType() == Material.ICE || b.getType() == Material.SNOW || b.getType() == Material.SNOW_BLOCK) {
                b.setType(Material.AIR);
              }
 else {
                break;
              }
            }
          }
        break;
case HELL:
      topBlockFound=false;
    for (int y=e.getWorld().getMaxHeight(); y >= Settings.sea_level; y--) {
      Block b=e.getChunk().getBlock(x,y,z);
      if (!b.getType().equals(Material.AIR)) {
        topBlockFound=true;
      }
      if (topBlockFound) {
        if (b.getType() == Material.ICE || b.getType() == Material.SNOW || b.getType() == Material.SNOW_BLOCK || b.getType() == Material.WATER || b.getType() == Material.STATIONARY_WATER) {
          b.setType(Material.AIR);
        }
 else {
          break;
        }
      }
    }
  break;
default :
}
}
}
}
}
}

Fixed version (ground truth):
/** 
 * Ensures that any block when loaded will match the biome of the center column of the island if it exists. Does not apply to spawn.
 * @param e
 */
@EventHandler(priority=EventPriority.LOWEST,ignoreCancelled=false) public void onChunkLoad(ChunkLoadEvent e){
  if (plugin.getGrid() == null) {
    return;
  }
  if (e.getWorld() != ASkyBlock.getIslandWorld()) {
    return;
  }
  for (int x=0; x < 16; x++) {
    for (int z=0; z < 16; z++) {
      Island island=plugin.getGrid().getIslandAt(e.getChunk().getX() * 16 + x,e.getChunk().getZ() * 16 + z);
      if (island != null && !island.isSpawn()) {
        Biome biome=island.getBiome();
        Biome blockBiome=e.getChunk().getBlock(x,0,z).getBiome();
        if (!biome.equals(blockBiome)) {
          e.getChunk().getBlock(x,0,z).setBiome(biome);
switch (biome) {
case MESA:
case MESA_BRYCE:
case DESERT:
case JUNGLE:
case SAVANNA:
case SAVANNA_MOUNTAINS:
case SAVANNA_PLATEAU:
case SAVANNA_PLATEAU_MOUNTAINS:
case SWAMPLAND:
            boolean topBlockFound=false;
          for (int y=e.getWorld().getMaxHeight(); y >= Settings.sea_level; y--) {
            Block b=e.getChunk().getBlock(x,y,z);
            if (!b.getType().equals(Material.AIR)) {
              topBlockFound=true;
            }
            if (topBlockFound) {
              if (b.getType() == Material.ICE || b.getType() == Material.SNOW || b.getType() == Material.SNOW_BLOCK) {
                b.setType(Material.AIR);
              }
 else {
                break;
              }
            }
          }
        break;
case HELL:
      topBlockFound=false;
    for (int y=e.getWorld().getMaxHeight(); y >= Settings.sea_level; y--) {
      Block b=e.getChunk().getBlock(x,y,z);
      if (!b.getType().equals(Material.AIR)) {
        topBlockFound=true;
      }
      if (topBlockFound) {
        if (b.getType() == Material.ICE || b.getType() == Material.SNOW || b.getType() == Material.SNOW_BLOCK || b.getType() == Material.WATER || b.getType() == Material.STATIONARY_WATER) {
          b.setType(Material.AIR);
        }
 else {
          break;
        }
      }
    }
  break;
default :
}
}
}
}
}
}