I’m trying to do run a model using modflow and flopy. I have the steady state model working good, however I would now like to add a transient head profile and see how the model changes. I’m a bit stuck in where to include the stress periods. I want to also do the particle tracking that should be affected by the moving head profile. I’m assuming for the particle tracking I need to change the ReferenceTimeOption to 2 but I do not know how to set the input properly [Period, Step, TimeFraction].