Prudential remand to consider non-instituted grounds is appropriate when those grounds were raised in the petition.
http://www.cafc.uscourts.gov/sites/default/files/opinions-orders/18-1180.Motion_Panel_Order.7-2-2018.1.pdf
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.