Propellant: there is a good margin (in case of aborted docking), but if the orbit is raised "too slow" there is the extra atmospheric drag and the orbital plane drift will be different from the ISS, so more propellant will be needed.No problem if it just takes much longer than planned.
There should be some experts that have gained enough experience with low-thrust maneuvers out there, after several ion-thrusted vehicles.
Or do they have any "fresh goods" on board that gets "smelly" after a week or two[*]?
[*] Batteries should hold - having working solar arrays. (RCS-)Propellant should be pretty stable - assuming no leaks. Anything I missed?