The 76L fleet will take along time for two major reasons.

1. It is such a large fleet. While all will be done by mid 2013, I would expect that the first one will be done a year or more before that.

2. The 76L fleet is getting more than just new seats. I have heard all new galleys, overhead bins, sidewalls, lighting...etc. Basically a total gutting of the aircraft. The 764 and the 77E do not need this total gut and therefore can just get new seats and be done with it.