If you have a Helper that you do NOT want to be included when you AutoFill
AND you do NOT want them to be able to pick up Unassigned Shifts on the Tradeboard:

• Set their Maximum Hours per Week to one (1)
• Set their Maximum Shifts per Day to zero (0)

If you want the Helper to NOT be AutoFilled
but you DO want them to be able to pick up Unassigned Shifts from the Tradeboard:

• Set their Maximum Hours per Week to zero (0)
• Set their Maximum Shifts per Day to zero (0)