Filtering Report by Old Custom Field Value

My team had to update a value in a dropdown custom field. We recently tried to run a report for a project that uses the modified custom field and noticed that in the default state of the report we see tasks with the “old” and “new” version of the custom field value displayed.

At first that seem fine because it preserves the "old" custom field value on the old tasks and the new tasks created after the change are using the "new" value. However, when we try to apply filters to the report, we see that the filter options only allow us to select by the “new” value. Even if we select the “new” value, the tasks with the “old” value are excluded.

So is there no way to filter reports by the “old” custom field value once it's been changed?