The source browser displays the last date of the most recent commit in the entire branch, rather than the current file's last modification date. See screenshot examples.
This does not seem like the proper information to display there. Instead the date displayed should be the last date the current file was actually modified. My reasoning for suggests this is as follows:
1) The timestamp shown when viewing the source of the file is the last time the referred file was pushed.
That means every file in the repository shows the same timestamp when using the source file viewer in bitbucket. In any regularly maintained repository, a single file changing and being committed and subsequently pushed would mean all files now show _some_other file's last change / commit date. Not the current file. That's seems confusing.
2) The user interface is confusing. The source viewer displays the date in the context of the current file. But in reality that date has nothing to do with the current file, instead its related to ANY other file that was committed and then pushed to the branch.
3) There isn't a way to even find the last modified date of the current file in the source viewer unless you click the commit selector dropdown - which DOES show the current file change commit history.
3b) Think about that for one moment - The element which you click to get access to the current file's commit history has the information that shows the most recent commit for the whole branch. Those two pieces of information are highly inconsistent with each other.
To resolve this issue the current modified date for the file should be displayed in the file browser. The current commit date of the branch should be shown somewhere else in the interface if that information is deemed still important.