There seams to be a lot of miss information around, so here goes.
The 777 is the first aircraft certified that uses composites for the floor beams.
As such the intial certification was EXTREMELY conservative. I am not sure of the exact number but something like the first 35-40 were certified under this restricted total life. The aircraft in question can be relifed but it is very expensive and involves the complete removeal and replacement of the floor beams. (May also apply to other structural members).
I am, not sure if it is ahrs or cycles limit.
As the production run was going on, and with more evidence as to the lasting qualities of the structures in place and prob some mods, the life of the aircraft was extended.
You will find that this only applies to the 200's, the 200 er's are not affected as they came out later. They do have life limits, just a lot greater.
EK have 3 aircraft approaching the same limit, they are looking seriously at a relife because we need the seats. However, we would be the first and that is always risky. A frieghter conversion was also talked about because you have the floor out anyway.
The 777 will be around for a long time, guess you could look at these first ones to go as sacrifices to the new technology
Watch out for gravity, ultimately it WILL take control