The question was poised on how to get both types of tickets (unplanned and planned) into a single project board.
After leading an Infrastructure Team, required to handle all outages (unplanned work) along with upgrades (planned work) we had to come up with a way to manage our efforts. We accomplished this with two projects.
We did this for two reasons, which I'll expand upon later 
The way we did this, was to use a filter query for the board.
WIP = 'work in progress' aka planned work or Agile
UP = 'unplanned work' aka Kanban style tickets
`project = WIP OR project = UP'
This allowed a board to show tickets from both projects.
Tip: Make sure you align all the workflow sections with a column so you don't have any 'missing' tickets 
As always, would love to here your comments 
Cheers!