The Fourth Circuit has determined that a federal district court has jurisdiction over a purely legal question related to statutory eligibility for asylum for the beneficiary of an I-730, even though ultimately, USCIS has discretion whether to grant the I-730. In this case, the legal question was whether the asylee spouse could qualify for asylum through the I-730 process when she was subject to a reinstated removal order.
The full text of Ortez Reyes v. USCIS can be found here: https://www.ca4.uscourts.gov/opinions/251391.P.pdf