I continue having new outbreaks, 44hrs after taking po Ivermectin for mild scabies, is this normal? Or does this mean tx has failed/isn't effective?

Consider the process. The break out of scabies develops with an immune reaction to the debris left by the living mite in its burrows. Once you kill the mite, it may take a few weeks for the intense itching and bodily reaction to fade, because the drug does not remove the triggering material form your body. I would give it some time before I consider it a failure.
Consider re-exposure. Ivermectin is highly effective for scabies. New skin lesions suggest you are having repeated exposure in your environment (such as bed, clothing, etc.). Carefully quarantine clean clothes that have been dried on a high setting. Consider using an insecticide "defogger" in your bedroom, and clean/dry all sheets, pillows, bed clothes at high dryer setting.