This could be an option, unfortunately a good chunk of the people who invest never seem to follow any of the news/announcements I make.
Some just send me their investment- log off forums/emails etc for months and then ask me later "so whats the word?" - which makes it difficult to make decisions for them.
Please understand I am saying this respectfully, with a smile on my face... Why are you trying to make a decision for them at all?
The people who bought into the group buy already made their decision. That decision should stand unless they specifically change it. I respectfully suggest: you should not think you need to make a decision
for them at all. They made their decision; respect it.
Your safest option is to accept "refund requests" by shares owned. As soon as you have enough "refund shares," get a refund of the last miner ordered and "slide" everyone else who remains in the group buy "up" to fill those emptied slots.
You don't need to make a decision
for anyone. Let those who have decided to get a refund, get a refund. The rest of your members' decisions should be left alone.
Thanks for being so thoughtful and concerned for your group buy members. It does you credit. But I think you are making this an all-or-nothing proposition when it doesn't need to be. Based on your numbers earlier in the thread, you already have enough refund-ready shareholders to get a refund for them. I'm making an assumption here, but if my assumption is right, why wait? Refund one or more of the miners in the second buy (so no one can be moved from buy #1 to #2) and send them their coin.
P.S. This method will make the refunders happy, and it will also cause some of the people in buy #2 to be very happy. They will "magically" find themselves "moved up" into buy #1, and not have to wait as long to begin receiving a return. Everyone gets to be happy this way. Just something for you to consider...