People just seem to lose their brains when thinking about converting to LED. It's almost like a religion or something where they "just have faith" that they are brighter and last longer even when faced with the reality.
I've regularly looked at converting 996 T-8 bulbs in one business every 5 years when they are due for replacement with 24x7x365 use. That is 43,600 hours but we have had some failures when we tried to push them to the 52,500 hours when replacing them at 6 years. The failure rate with LED is too high, the light drop off too fast, and minimal cost/energy savings. All the cheap LEDs fail way too fast and since the phosphors are similar to florescent that give them a pleasing CRI, they get ugly with time. Anyone thinking of using LED as a way to stop replacing bulbs is using the wrong florescents or just hasn't seen the effect of their misjudgement yet.
I am saddened just about every time I go to Costco and see some fool loading up a cart with a bunch of $20 LEDs. Those units make a lot of sense when you buy one or two for task lighting and temp use but when you buy 30 and start using them for shop lights, you are a fool. I stuck 4 in an area for temp use until we could have lighting added in that area. In 2 years, the lighting fall off is noticeable. They will clearly hit the garbage before making it 4 years.
I changed over 6 offices, each with four 2 lamp florescents. I used a different brand of LED conversion of each. After 3 years, every office has at least one dead bulb and several have partly dead lamps also. Maybe worth doing the conversion as they were T-12 originally, the conversion would have been a horrible failure if they had been T-8 fixtures. Not to mention every office lost some light and most required careful rotation of the LED bulbs to give acceptable lighting. T-12 and T8 have even light, not the overly directional crap of LEDs.
Here is what gains you light: CLEAN Fixtures & covers and any NEW light fixtures. Also critically important is GOOD florescent bulbs, not the crap at the BORG.
LEDs are working out pretty well in less used areas with motion sensors. LED have some real advantages in lights that go on/off many times a day.