I have cloned a coin and changed some variable to make it my own coin. I have launched it and have a few mining pools mining my coin. Going through the code I notice I have an error and the reward halving starts over at block 10k. So miners are getting 500 coins per block instead of 250 coins. I believe this sort of change would fork the coin to a new blockchain but I want current holders to keep the same amount of coins on the new fork. How can I change the code and fork the chain to comply with the new info?