Beginning at 8:00am PST on November 15th, Coinbase will pause BCH sends & receives and buys/sells. We're taking this step to minimize customer disruption during a planned hard fork on the BCH network.
When the upgrade is complete, we will evaluate the network and take appropriate next steps. During the pause, your BCH will remain safely on Coinbase.
For more information, please read https://blog.coinbase.com/what-to-expect-during-the-bitcoin-cash-hard-fork-f15fd03687db