Mirroring a Mirrored Column

My boards are set up as follows - 1) Project Boards 2) Team Portfolio Boards 2) Enterprise Portfolio Board.

Not all teams will have individual project boards. For the teams that do, The project timelines are mirrored up to the Team Portfolio boards. For those that don’t have project boards, timelines are input directly on the Team Portfolio Board. I would like to mirror up all timelines on the Team Portfolio Boards to our Enterprise Portfolio Board. However, within my Team Portfolio boards, I technically have two different column types - Mirrored columns and Timeline columns. Currently it is not possible to combine the information from these two column types in a mirrored column on the Enterprise Portfolio Board