This Date table contains several date offsets and boolean filters that you could use in measures or in the filter pane on either report, page or visual level to stop values from projecting forward.
The latest version of this extended Date table is available in this thread.
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To determine what YearMonth you’re in is very simple with the MonthOffset because that value (actual month) will be equal to 0, to stop projecting forward all MonthOffset values should be less than 1.