We, Kolkata based plant, place 2 separate POs on 2 Chennai based parties.
Party A to supply Mandrel . They will deliver it at Party B, who would supply cooler gear box but additionally to perform job work. Party B to assemble mandrel ( supplied by A) and then to send to Kolkata.
As Party A will issue invoice to Kolkara but ship to Chennai Party B along with Igst, can Kolkata plant take igst credit on release of payment to A immediately? Job work and payment to B plus final supply to take 3 more months