Poloniex is now announcing the will re-enable Steem and SBD July 1st at 1 AM then 4:00 AM Eastern Updates as I can post them below. Some SBD and likely Steem deposits are being reported as received from various users history updates and more below.
As of early July 4th Poloniex now says....
STEEM is currently under maintenance or experiencing wallet/network issues. Deposits and withdrawals will remain disabled until a solution is found, which may require an update from the STEEM team. Any updates must be tested and audited before enabling.
SBD is currently under maintenance or experiencing wallet/network issues. Deposits and withdrawals will remain disabled until a solution is found, which may require an update from the SBD team. Any updates must be tested and audited before enabling.
Price action suggests a significant amount of users have gotten new funds available and have executed trades for other currencies.... or perhaps a few users with a significant volume...
EDIT: The original time Poloniex gave was 05:00 UTC. Later showed 08:00 UTC. Previouslyshowed:
STEEM deposits and withdrawals are currently estimated to resume by 16:00 UTC on July 1st.
SBD deposits and withdrawals are currently estimated to resume by 16:00 UTC on July 1st.
No updates on twitter. The original time table for local times are no longer valid. I have removed them for now. I will update with a new table later if needed.
I'm not holding my breath... but lets see how this pans out... if they do not get things fixed... (we must have some patience here tech can be tough to troubleshoot) we should start pressuring the witnesses to put the heat on Poloniex...
I am also getting reports from various users that SBD deposts are starting to show up in users accounts. I will look into a test for Steem and SBD. Also a report from 
Updates to see if they have re-enabled
04:50 UTC July 4 - API, Wallet and Exchange pages are still showing as disabled.
16:41 UTC July 3 - API, Wallet and Exchange pages are still showing as disabled.
21:06 UTC July 2 - API, Wallet and Exchange pages are still showing as disabled.
15:43 UTC July 2 - API, Wallet and Exchange pages are still showing as disabled.
07:04 UTC July 2 - API, Wallet and Exchange pages are still showing as disabled.
02:37 UTC July 2 - API, Wallet and Exchange pages are still showing as disabled.
18:32 UTC July 1 - API, Wallet and Exchange pages are still showing as disabled.
14:56 UTC July 1 - API, Wallet and Exchange pages are still showing as disabled.
06:57 UTC July 1 - API, Wallet and Exchange pages are still showing as disabled.
06:33 UTC July 1 - API, Wallet and Exchange pages are still showing as disabled.
06:24 UTC July 1 - API, Wallet and Exchange pages are still showing as disabled.
06:01 UTC July 1 - API, Wallet and Exchange pages are still showing as disabled.
05:45 UTC July 1 - API, Wallet and Exchange pages are still showing as disabled.
05:23 UTC July 1 - API, Wallet and Exchange pages are still showing as disabled.
05:07 UTC July 1 - API, Wallet and Exchange pages are still showing as disabled.