According to the official announcement from Zcash(ZEC), ZEC is set to undergo a hard fork activated at block 347,500. It is estimated to happen around 9:22 on 26 June 2018 (UTC+8).
In order to protect our users’ assets, OTCBTC will suspend ZEC deposit and withdrawal services from 21:00 on 25 June 2018 (UTC+8). The services will resume when the hard fork completes and we can confirm it is stable.
For more information, please go to https://z.cash/support/network-upgrade-guide.html
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