Do you know the difference between REIL and RAIL? Of course, you do, so that's not the question. Plus, the Brainteaser author isn't nice enough to continue in that Mr. Rogers tone and, instead, requests that you decode REDL in this partial NOTAM:

Ailerona IA [IA66]: February NOTAM #999 ... Runway 18/36 REDL OUT of SERVICE February 14th, 2016 ...


Runway end light


Ramp edge light


Runway edge light


Runway end light

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