The features we need to apply is fill area under spline.

The common solution on your forums suggest holding another series with type ‘areaspline’
and give it the corresponded points we have 2 problems with this :

1) We are holding huge amount of data on real time updating timeline and we don’t want to hold another series
with the same points count (even if the most of them are null) just for color small area from time to time

2) The ‘areasplin’ does not correspond the ‘spline’ Bezier curve it exceed from its frame as showing below

current workaround supplied is http://jsfiddle.net/HWKwa/18/

It would be best to have api overload addPlotBand

something like addPlotBand({options, color etc.},from,to, series)

Thanks in advance