The patch list can be found on the forums.
Starting from roughly 12pm on Thursday the 11th of September (Server Time) there will be a scheduled maintenance, this will be to implement a new update + perform maintenance. There is no estimated time on how long it will take to complete, however at a rough guess I would estimate 2-3 hours assuming the are no problems.
Starting from roughly 1pm on Monday the 23rd of June (Server Time) there will be a scheduled maintenance, this will be looking at improving some aspects of the database. There is no estimated time on how long it will take to complete, however there will be events in place once the server is back online.
Update: There were a lot of issues I wasn't expecting, however hopefully the database should be running smoother now. The Siege Leaderboards have also been cleared to remove the D/C that would occur when viewing it.
There will be 48 hours of 2x Red Chips, 2x MQC and 2x Vote Rewards until 9pm Wednesday the 25th server time. Happy hunting and questing