Start with the rotation
Pitman, Dupont, 24/48, night shifts, and on-call work all create different custody constraints. Map the work pattern before choosing the parenting pattern.
Protect recovery time
A safe plan accounts for the hours after a long shift. Recovery windows should be visible, not negotiated at the last minute.
Write backup rules
Mandatory overtime, callbacks, and late schedule changes need a default handoff rule so every change does not become a new conflict.