Order of x1values argument in fcPlot() and maPlot() only switches axis label, does not alter y-axis values

[sgaluh]

Hello, I am using the function of fcPlot and maPlot to compare 3 treatments (Veh, cort10, and cort1000) in control and patient.
I notice that the y-axis values in fcPlot or maPlot remain the same if I compare cort1000 vs. veh or veh vs. cort1000. I would expect that the y-axis values would change in respective order. Do you have any suggestion here?
Thank you in advance for your advice.