I don't think there is such a precedent. Tezos being a completely new product with a completely new code base (and new smart contract language) means there's actual work to do that hasn't been done yet. (though its been under heavy development since 2014) I've not seen an official functioning wallet or official blockchain explorer.
The developers have said they were hoping to get coins released in about 4 months but if this runs along like every other software project I'd give it 6 months...
I'm glad this is flying so far under the radar, largest ICO maybe but from what I can tell, hardly anybody realizes this is a completely new product. I suspect most people think this is like the other 99% of ICO's recently, some copied solidity code from github and some poorly conceived business idea. I hope it does crash on the exchanges, I feel like these opportunities (having watched this space since 2014) rarely happen.
I've popped in week after week for years and its the same copied code re-branded with new names and logos over and over. There are just a few new products every couple of years it seems. (Probably because real projects take years and years to develop unlike things like Bancor or the thousands of other 'assets' you see available which can be thrown together in a weekend.)
TEZOS has source code on gitbub. The DEV team is working, but I think a project will take time to develop. Rest assured it will be released soon. May be April