I will be filing 2016 taxes and owe ~$5575.00. I will receive a 1099C for a transaction that ocurred in Feb/Mar of 2017. Should they be combined?
No. If the debt is canceled in 2017, that will be reported on your 2017 tax return.
Cancelled debt is almost always taxable but there is an exception if you are insolvent or bankrupt when the debt is canceled. Now is a good time to start reading the rules and collecting proof.