According to a forum post, the long-awaited Patch 3.7 is scheduled for release on May 21.
As a result, ranked queues will be closed from 2.30 am (GMT +8) and servers will be taken offline from 4.00 am till 7.00am to allow patching.
Patch 3.7 Preview Video
Players can click here to find the full Patch 3.7 changelog.
Source: [Garena LoL]
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