If it is for just the Current Version, you can change the formula scope to Current Version, but if you want all of them, you can do this:
Create a module dimensionalized by Time and Versions, with one line item. I have it defined as Date, but it could be anything. Format should be Period with the summary being either First Non Blank or Last Non Blank. The formula should be: IF ISBLANK(PREVIOUS(Date)) THEN ITEM(Time) ELSE PREVIOUS(Date)
Then, the fun trick is to change the Formula Scope to All Versions except Actual.