The Ethereum "Arrow Glacier" network upgrade is scheduled to take place when the block height reaches 13,773,000. This is predicted to occur on Wednesday, December 8, 2021.

The upgrade changes the parameters of the Ice Age/Difficulty Bomb, pushing it back several months. For more in depth information, please refer to this article.

In preparation for this upgrade, Poloniex will be disabling Ethereum wallets (deposits and withdrawals) on December 7th at 18:00 UTC. Wallets will resume regular function after the upgrade has been activated and the network is deemed to be stable.

Update:

We will also be disabling all ERC20 based tokens in anticipation of the "Arrow Glacier" update occurring at block 13,773,000. Wallets will resume regular function after the upgrade has been activated and the network is deemed to be stable.

December 03, 2021