Dynamic filter conditions in interface

I’m hoping to create an activity tracker across my different consulting contracts. The hierarchy for submitting an activity is as follows:

Contract 1 > Possible Tasks (“WBS”) → Activity related to task
Contract 2 > Possible Tasks → Activity related to task

In an interface form designed to submit a user activity for a task/contract, I’d like to filter a drop down of WBS possibilities based on a user-selected contract.

I understand this feature doesn’t exist yet; is it currently in development? I see that I’m not the only one that has sought similar functionality across airtable features.