The command "atlas-run-standalone.bat --product jira" worked fine in the Plugin SDK 4.2.0.
In 4.2.1 this does not work anymore but maven complains that it cannot parse --product.
In 4.2.0 the commandline parameter was translated (like others similarly) to "-Dproduct=jira".
In 4.2.1 this translation was removed, but the help and tutorials still refer to the --product syntax.
So either the batch file (and others?) should be changed back, or the documentation needs to be updated in that file and on the website in tutorials like https://developer.atlassian.com/display/DOCS/Explore+the+Installed+SDK+and+the+atlas+Commands