Block.one’s EOS will complete its year-long token crowdsale later today, becoming the largest initial coin offering (ICO) in history having raised a total of over $4 bln.

The highly-anticipated formal release of the accompanying software, which proponents claim will constitute a decentralized operating system for large-scale decentralized applications, will also see developers prepare token migration to new EOS wallets.

The move is significant, EOS having fallen victim to mounting suspicion over its long-term efficacy as well as its token’s genuine value in recent months.

Among critics was Dogecoin creator Jackson Palmer, who in April went public to quell excitement on social media regarding EOS’ upcoming release:

“...[A]ll these people who are excited about ‘EOS launching soon!’ somehow don't understand that ‘launching’ simply means the code will be available for use. There is no ‘network’ being launched that you can then go and use, or redeem EOS tokens on.” He also tweeted:

Exchanges have suspended EOS deposits and withdrawals during the EOS mainnet token swap. OKEx and Bitfinex have both announced that, while deposits and withdrawals will not be unavailable, trading will be unaffected throughout the swap. OKEx also reminded users not to deposit EOS into the exchange during the suspension, or their tokens will be irretrievable.

Confusion over the token registration process led one community member to publish a guide on generating an EOS key pair and how to map to the Ethereum address containing the EOS tokens.

Despite criticism and confusion, the crowdsale easily dwarfs any ICOs before it, even in comparison to Telegram’s now-curtailed offering which raised a reported $1.7 bln.

Meanwhile, the EOS price has remained stable around $12 in the run-up to the release, having peaked at over $21 in late April.