I assume the field 'y' is an incident field? Changes to incident fields only allow Incident-level playbooks/rules to run. Currently there is no mechanism to evaluate incident sub-objects, like tasks, in an Incident-level playbook/workflow. It is definitely a gap that we would like to fill.
It may be possible to build an incident-level playbook that runs on changes to field 'y'. Then use Functions to see if there are any of Task 'X'. If so, change a property on the task which will then trigger a Task-level playbook.
Alternatively, if it is possible to wait adding task 'x' until after field 'y' value is present, may be an option.
Ben
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Ben Lurie
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