And thanks for a reply - yes that would make sense and I would do that if the rules were separate..
In this rule, both conditions need to be met at once in order to have free shipping, not one or the other...
eg.... If the free postcode is set to true, but the cart subtotal is less than $150 then no free delivery
if Cart contents is over $150 but the Free postcode is not set - no free delivery.
Only when the cart subtotal and the free post condition is met - does the client get free shipping