No Sweat. Mom (Debi) has your back. You are probably in the process of working through the plateau. But you don't want to stay at the 140F level too long, for health reasons. If in doubt follow her directions and move to the oven this time. Better safe than sorry.
It YOU ARE working on up to higher temps, be patient and ride it out. I think you will be fine.
Hope you have a probe thermometer for internal breast and thigh temps. If so, let them be your guide. If not, then you may want to borrow a manual probe type from a neighbor, so you know where you are at.. Just guessing isn't a good thing.