I've had an HP ZR2740 IPS LED monitor about 16 months now and I'm noticing it's not as bright as my newer twin Dell Ultrasharp 2412s which are about 8 months old.
Full Disclosure I use all my screens MAX brightness and NEVER turn them off. I mean literally I think they've been set and running at max brightness and contrast since they left the boxes. (only now finding out that may speed up aging of the backlights)
That said I work in a very bright environment and can not tolerate lowering the brightness in fact most monitors below 300nits are simply unacceptable so essentially I'm asking 2 questions...
1. Is 12 000 hours or thereabouts enough wear and tear that might require a backlight replacement.
2. Is such a procedure offered anywhere or am I faced with having to replace every 18 months assuming I can not work with lower brightness and contrast settings?