It’s possible to replace an entire array or sequence too. In the previous example, if the Octopus variable foo:bar was set to ["baz","qux"]
So for the JSON shared above, setting an Octopus variable called Services with a value including the array e.g. ["service1","service2"] will replace the entire array value, alternatively you can target specific items in the array using indexes in the variable name e.g. Services:0: instead.
Hope that helps but feel free to reach out with any questions or issues at all!