[NMS] Returning a custom PacketPlayOutBlockChange to its original block

Hi there,
I'm working on a plugin that uses PacketPlayOutBlockChange to change a player's surrounding blocks to rainbow wool colors and am not sure how to change them back to the original block. I'm assuming there's some packet I can send to refresh the blocks/chunk?

Code:

                  
PacketPlayOutBlockChange packet =
                            new PacketPlayOutBlockChange(nmsWorld, new BlockPosition(x, y, z));
if (new Location(loc.getWorld(), x, y, z).getBlock().getType() != Material.AIR) {
    Block b = ((CraftBlockData) Bukkit.createBlockData(getRandomWool())).getState().getBlock();
    packet.block = b.getBlockData();
    ((CraftPlayer) p).getHandle().playerConnection.sendPacket(packet);
}