Using a Condition on a Choice Column (Kanban Board)

I'm sure I'm not the first person with this situation, but I couldn't find a similar post, so here goes:

I have the following sample data from a SharePoint list that contains travel data.  The end goal is to have a Kanban board where the bins are the [Time Out] column (i.e., 7 days in, 14 days in, 30 days in, 30 days out).  The [Time Out] is calculated based on [Start Date].  Therefore, [Time Out] is a discrete set of four values, just calculated.

I know that a Kanban board can only use a Choice column as the bins.  Is there a way where I can use something like [Time Out], where it automatically calculates how far away Start Date is from today and still use it as a Kanban board bin?  The following is the simplified list data.

The column [Time Out] is just nested IF statements comparing Start Date to Today.

...and this would be the final structure of the SharePoint Kanban board.

Thank you very much!