I want to run a private ethereum blockchain.
What I want is I want to distribute certain number of premined ethers (say 20 million) among some accounts. If I initially keep the difficulty high, It will take too long to mine the blocks and get the required rewards.
Is it possible to premine certain number of blocks and then increase the difficulty level? Will I have to stop the geth instance to adjust the difficulty level? and If I stop the geth instance in between, How can I continue mining over the previous blockchain with a different genesis blocK?