Ive had this mission twice now, and im unable to transport off the mission to an alliance building (I only transport to alliance buildings I have no cells of my own)
Couple questions :
1.) can sheriffs transport now? I thought they cant but my one had a status 5 for transport BUT it wouldnt allow transport of prisoner. NONE of my alliance buildings show for transport for prisoners when I get this mission. I can transport to alliance buildings on all other missions
2.) I cleared all my units, Sheriff that had the transport request and my fire marshals and I was hoping prisoners would transfer to a patrol car see if I could transport then but they did not. Can I not cancel units to transfer prisoners to a squad I want them to be transferred in off a mission?
I currently have 4 patrol cars and my transfer status only shows my police buildings with no cells available as I dont own any, Why wont it show my alliance cells like it does on all other missions?
3.) I know fire marshals can transport if only 1 personnel is assigned, this is true, correct?
4.) should I only assign 1 personnel to my sheriff deputy's and fire marshals? I try and assign a full squad for faster mission outcomes. But if this issue is continuing for me on this same mission twice now im starting to think I should?
Im confused. This is the only mission Ive had this issue with and its the second time 
I end up releasing prisoners because transporting is impossible.
Edit: im going to keep this mission up to see if I cant resolve it somehow with some help.