This works for the range aspect of your question (eg choosing 17-20 Jul)
It distinctly does not work for the "Presets" or "Relative" options from a time picker
When you select a date range from a time picker, you’ll get a pair of Unix epoch times returned
If you subtract $picker.earliest$ from $picker.latest$, multiply by two, and assign the result into a new token (eg "$evenearlier$"), you’ll get the following inside your dropdown’s XML:
<change>
<eval token="evenearlier">($picker.latest$-(($picker.latest$-$picker.earliest$)*2))</eval>
</change>
Then, down in your query, do this:
<earliest>$evenearlier$</earliest>
<latest>$picker.latest$</latest>
from User warren – Stack Overflow https://stackoverflow.com/questions/39204162/splunk-calculate-time-and-doubling-it-from-the-user-selection/73082133#73082133
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