So, yes complete, sign and upload a new I-864 using the recently new version of the I-864. Ignore the step children for now, but if your income is barely enough to qualify for them, yes, do state and document your liquid assets and add your husband's income (converted to dollars) in part 6, line 8 and provide the evidence this income will continue, and evidence of his current income, like a pay stub, or best, just the offer letter accompanying his job transfer.