I am afraid that I do not understand what you are trying to achieve.
When an axis is attached to a series, the axis automatically adjusts its range in accordance to the data of the series. So you should not need to do any additional work to get this behavior - when the items source of a series changes - the axis of that series will adjust its range automatically.
When the number of series in the chart changes - the legend items are updated automatically, so here you again do not need to do anything additionally.
Let us know if you need assistance with anything. If so, please send us a small project that mimics your actual scenario. We need a small project and not your actual application, as it will be easier for us to assist you. Also please describe what you get right now and how you would want it to behave. Thank you.
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