I got an email from the exchange I use stating the Istanbul hard fork is to occur at block 9069000 at approximately 15:44:36 PST on December 7. It happened already but they have suspended all deposits and withdrawals from happening until further notice.
It is not a contentious fork and so does not result in any new coins from it happening.
So why would they decide to suspend all transactions of ethereum?
It is interesting. I previously read that improvements to ethereum called Istanbul were due to happen on December 4th. Therefore, after this number I searched for news on this subject and could not find it. Yes, separation from ethereum of new coins is not planned yet. Could the suspension of trading on the exchange be connected with something else, and not with improvements in ethereum?