[NittanyLion]

if LEX is on eastern daylight time (are they? I don't know), it would still be dark at 6:00am.

They appear to be on eastern time.

[NittanyLion]

Some interesting text on the construction project at LEX here.

Phase III
In this phase, the construction of new pavement begins on the runway safety area, taxiway and emergency access roads at the end of Runway 4. Phase III also includes the relocation and installation of numerous navigational aids and runway approach lighting.

Phase IV
Phase IV includes an asphalt overlay of the entire length of Runway 4-22 and Taxiway A. All pavement lighting will also be replaced.

One wonders whether this ongoing construction will be a contributing factor...