Hi PTC77. i happened to call tcm today to ask the same. that guy told me need 3.3L and ask me to bring 4L. Hence, i guess you will need 4 bottles of Amsoil. Perhaps, the left over + another 3 new bottles will be enough for your subsequent change.
may i know if you have been using Amsoil? Im going for my 30K svc and intending to use Amsoil SSO 0W30.