Multiple levels with different steps for contour series

Currently we have options to configure the splits of the contour area splits like below,

contours: {
coloring: ‘fill’,
showlabels: false,
start: 0, # Start Value
end: 1, # End Value
size: 0.02, # Size of the split … so for the give range and size 50 splits will be there

But, it seems there is no option to configure multiple size for different ranges…
size 0.02 for 0 to 0.5
size 0.04 for 0.5 to 0.8
size 0.08 for 0.8 to 1

please let me know if there is any existing way to customize the rage and size like above…