By Dave Sebastian 



  Delta Air Lines Inc. said it has upped its offering with SkyMiles IP Ltd., its loyalty subsidiary, by $2.5 billion to $9 billion, offering a cash infusion amid the depressed air-travel environment during the Covid-19 pandemic. 


  The company said it expects to issue $2.5 billion in 4.5% senior secured notes due 2025 and $3.5 billion in 4.75% senior secured notes due 2028 on Sept. 23. Delta and SkyMiles also expect to enter a credit agreement for a $3 billion term-loan facility. 


  Write to Dave Sebastian at dave.sebastian@wsj.com