Section 18 (Bar of Jurisdiction) provides that after the 'appointed day', which courts/authorities retain jurisdiction over matters under Section 17?

Section 18 creates a bar of jurisdiction: from the appointed day, no court or other authority shall exercise jurisdiction in relation to matters under Section 17, EXCEPT the Supreme Court and High Courts exercising jurisdiction under Articles 226 (writ jurisdiction) and 227 (supervisory jurisdiction) of the Constitution. This preserves constitutional remedies - writs of mandamus, certiorari, and prohibition can still be issued against DRT orders by High Courts. All civil courts are completely excluded. A specific savings clause (added by Act 1 of 2013) preserves recovery proceedings relating to multi-State co-operative banks pending under the Multi-State Co-operative Societies Act before the 2013 amendment.