will be great if one of the devs will answer here to clear this question marks....
Devs can not provide an answer concerning the continuation of mining on the legacy chain ... Simply put, a chain lives as long as there are people mining (on) it. A chain lives means that there is a coin. So, either the non-obelsik miners stop mining and then the legacy chain will die, or they continue mining and it will live. Obelisk miners will mine on the hard forked chain (the new main chain). Given the fact that I don't think non-obelsik miners will be willing to throw away their equipment, it's highly probable they will continue mining on the legacy chain.
There will be only one chain, not two
Sia will still be blake2b coin
https://blog.sia.tech/sia-fork-faqs-c6b3e0e73ce0yeah, but I'm still betting the other 4/5's of all blake2b miners which are NOT obelisk's will fork to a new coin. Likely just go with the old chain and call
themselves 'Siacoin Classic' would be my bet as the most likely. It is that or they are all Doorstops on Nov 1st, 2018. That won't happen.
brad
Siacoin classic is almost a certainty, people don't like losing money, and setting up a pointless coin isn't exactly frowned upon in the crypto world, the miners with obsolete hardware can either lose money or start a new coin with almost zero effort, all they need is a good meme, their community is already here. I say good luck, Doge 2.0