Your questions was answered in the support ticket related to the same behavior that you post in our ticketing system. However, I will paste the answer in this forum so that it can be available for the rest of our community.
As a side note, please try to keep the communication on a single thread. This will help us to organize our history and assist to our customers better.
"What you are describing sounds like a result of a fix we made some time ago. The behavior you observe is actually expected.
The axis keeps a collection of cached labels (content and template). So when an old content is present - the template is not reevaluated. When a new value appears - the template selector is called to get a template, and the new value-template pair is cached. Previously the template selector was used too often, every time the chart was resized, panned and zoomed. I hope you understand that this is a very nice improvement we made.
If you need new templates for the new zoom level you have (or data range) - you should set a new LabelTemplateSelector whenever you need a different template. Note, you should only change the LabelTemplateSelector when you require new templates, otherwise if you change the template selector too often - the optimizations in the axis will not work."
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