This information can usually be approximated from What's New for Atlassian Cloud, i.e. Bamboo Cloud is running 5.11-OD-02 as of April 18. Aside from tracking the release notes, you can also check the latest Application Versions directly, but please note the info at the bottom:
Your site may be upgraded a day before or a day after the date shown, as upgrades are rolled out progressively to different regions. See Maintenance windows for details.
Agreed, that's what one would expect - this used to be in the footer of each page, and while I can understand why Atlassian has removed it there, it should really be surfaced in the admin section somewhere (it is in JIRA Cloud btw., but as far as I know not in Bamboo Cloud indeed, other than in Bamboo Server).
Make sure none of your agents is busy with any builds, then you can try this:
Bamboo Administration -> Plans -> Move Plans
Find this warning at the top of the page:
"It is strongly recommended that you ensure that all agents are disabled before you perform the move. disable all agents"
"disable all agents" is a link. Click it. It will trigger an internal server error. An error report will be displayed in your browser. It will include full version, build and build date of your instance.
One bug, that really IS a feature.
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Bamboo 5.9 will no longer be supported after June 12, 2017. What does this mean? As part of our End of Life policy, Atlassian supports major versions for two years after the first major iteratio...
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