We ran in to this a couple of years ago and were told that what you are trying to do is not possible due to a bug. (Apptio Support ticket- 00316269 opened 9/19/2022) I thought I could set the column formatting and then add in time and it would work- but it does not work that way. Instead, you have to add in time and then set each of the columns with a highlighting formula specific to the time column.
I am only using one value so my columns are just Month/ Year. I have to go in each column and do a specific highlight formula for each with the month/year. And each new year that i open i have to go in and configure the report. It is a workaround but not ideal. I'm not sure how I would do it with two values in the report....may have to play around with the name of the column heading format in the rule.

Each column has to have its own highlight formula entered after time is added in.

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