Wow, sounds like a crazy test. Your holding it at 6K rpm for 23 hrs straight?
12mins @ 800 to warm up, then RPM ramp up to 6k over another 6 mins, engines ran for 22.5 hours @6k then brought down to idle over the last 12 mins test was a 5 day run for a total of 110 hours @6k. Engines were then tore down and check for issues.