Actually, if you read the quoted article more closely, you will see that the B777 was never promised for LBA:
the possibility of securing the B777
Page 3, towards the bottom
Also, page 4 says advanced discussions with PIA were taking place to facilitate the introduction of the B777, and that no definitive date of the introduction was given
To me it seems like PIA have said they will try and get the B777 into LBA, but didnt go as far to set it in stone.