New clues emerge toward possible life on Enceladus

You would need to be able to predict when and where these plumes will take place and then calculate the orbital maneuvers needed to intersect the spacecraft with those plumes. This will be very hard to achieve with a 1+ hour communication delay. Most likely you'll have to rely on some autonomous AI based on some sort of reinforcement learning algorithm. Also, orbital maneuvers that involve changing the orbital plane are very expensive in terms of fuel consumption. So first there will have to be an observation stage to determine which orbital plane is most likely to encounter a plume and then explore various orbit trajectories inside that plane until enough samples are collected.