Hello. Can some one please tell me version 11040 will be released?
11040 refers to an experimental pre-release that was released some time ago and available from https://www.sumatrapdfreader.org/prerelease.html the next formal release may be be 3.1.3 or greater (most likely 3.2) however only time will tell
is there and ETA for the formal release yet?
There rarely is The criteria is a significant update and since no-one is adding significant updates it will be after that point and then some time in the future see https://github.com/sumatrapdfreader/sumatrapdf/wiki/Release-process and Next Release of Sumatra PDF with new UI design and elements