The testnet genesis block itself will hopefully launch perhaps by the end of next month or at the beginning of April pending there is no unexpected development.
One expected development is the audit results in a few days which will let everyone know how much work is needed to get out the testnet.
According to notes, “the aim is to get out the updated spec as soon as possible, taking into account the audit, plus some networking updates.”
Danny Ryan, the ethereum 2.0 coordinator, presumably is working closely with auditors so the v.0.11 spec might go out this month depending on how much work is needed.
The three main clients, Lighthouse, Nimbus and Prysmatic will then incorporate the spec updates and so finally get out the testnet genesis block.
Nimbus and Lighthouse are both hiring with Lighthouse stating they’ve received 20 applications. Lighthouse as you might know is mainly supported by Ethereum Foundation grants so their income is pretty secure if they keep doing a pretty good job, while Nimbus is financially backed by Status, the ethereum browser. Prysmatic is from ConsenSys.
Lighthouse is now ready to merge v.0.10.1 and are preparing the 100k single-client testnet with a focus on optimizations.
While Nimbus has just ticked off one of their milestones after some work related to networking was merged with Justin Drake, an ethereum 2.0 researcher, giving them a pretty tight timeline.
As stated the testnet genesis block is expected at least by early April, with it to perhaps launch at Edcon in Vienna.
If the MVP goes out in just a few weeks, then they should perhaps be able to make it, with this testnet needing three months to run.
The deposit contract will then launch a month after, probably at the Ethereal Summit in New York during May. The target date for the live mainnet launch is July 30th.
All are tentative dates that might change, but the above is the current stated plan with the first indication of whether it can be met being the launch of the v.0.11 specification which gives the green-light for the multi-client testnet.