I have been following Concordium for over a month now. Early this month they released their Testnet 2. Concordium claims and even proves to be the next-generation blockchain for enterprises and the first with user ID verification built-in at the protocol level, has released its Public Testnet 2 and an updated White Paper. Thier Testnet 1 was released In early April 2020.
They are currently working hard on the implementations of the specifications coming out from Concordium's new scientific research around protocols in P2P, Consensus, Finalization, Cryptography and Smart Contracts.
The Testnet is a grounds for continuous deployment of Concordium's latest work, where simulations and diagnostics are run to help qualify and further tune the implementations.
They have a Concordium Network Dashboard (
https://dashboard.testnet.concordium.com/ ) that provides a live overview of nodes, consensus, finalization and performance metrics.
Their Testnet documentation is available at :
https://developers.concordium.com/testnet/docs