Thats pretty much what I always thought, that the moment of salvation, is the time one receives all of the Holy Spirit, one will EVER get. I call that, the baptism of the Holy Spirit, but the filling of the spirit, happens throughout ones life. Just my opinion, but I think our rewards in Heaven, are for all the times we were filled with the Holy Spirit. Just an opinion.
Not only do we receive all of the Holy Spirit at the moment of salvation, but we are also sealed with the Spirit. The calling and gifts of the Spirit are irrevocable and He puts His imprint or seal on us as a sign of the done deal...
Your opinion is a certainty, according to Scripture and according to God’s attributes.