We are announcing an upgrade of AMB and OmniBridge bridge contracts on both sides of the bridge: the Ethereum Mainnet and the xDai chain. The upgrade will happen on 29th of November.
The version of the contracts that will be used for the upgrade was audited by Quantstamp recently.
The main goal of the upgrade is to prepare the Arbitrary Message Bridge in general and the OmniBridge particularly to the migration to the same scheme for relaying messages from the xDai chain to the Ethereum Mainnet as the xDai TokenBridge uses: users no longer need to rely on bridge oracles to relay confirmations of the messages collected on the xDai chain side to the Ethereum Mainnet. It will provide additional decentralization and control for bridge users. You can get more info how it works on the xDai TokenBridge here and here.
The upgrade of the corresponding contracts for the test AMB bridge between Kovan and Sokol was already done.
It is important to note that the migration to new functionality will not be enabled just after the contracts upgrade. The plan is to switch the oracles and contracts to new scheme is the second half of December. This time will be used to implement the corresponding changes on the OmniBridge UI side and the AMB Live Monitoring app.