Accessing indicators from X bars ahead when shifts are applied

Hello,

Is it possible to retrieve the value of an indicator from X periods in the future (obviously with a shift applied to the indicator)? For example, the Alligator indicator with the following shifts applied (standard parameters):

ali = Indicators.Alligator(13, 8, 8, 5, 5, 3);

• Jaws
  • Periods=13,
  • Shift=8
• Lips
  • Periods=5
  • Shift=3
• Teeth
  • Periods=8
  • Shift=5

To retrieve the Lips value from 1 bar in the past I can do:

ali.Lips.Last(1)

But when I try to retrieve the Lips value from 1 bar ahead it returns NaN:

ali.Lips.Last(-1)

On the chart the indicator values are available for X bars ahead (8, 3, 3 in this case). How do I access these values from X bars ahead from a cAlgo Robot? 

Thanks