Only they can tell you. Box 1 of form 1099-C is the "date of identifiable event", in your case, the date the settlement was agreed to and the amount of forgiven debt determined. I can't find a due date in the IRS instructions, I may be looking in the wrong place, but other web sites claim the deadline for submitting a 1099-C is March 31.
In any case, you are required to report your canceled debt even if you don't get a form. If you later get the form. you won't have to report it again.
