As usual you can find the best answer here (had to use google though to find this thread as it would not come up with the internal search engine).

after speaking to both Qatar and BA asking about Bronze (Ruby) seats selection that was not working and being told all sort, I asked specifically if it was 7 calendar days or 168 (7x24) hours from departure and was told 7 calendar days… well I have two hours to go and then will be sure but this thread is already reassuring.