Correct. But that is hardly Trinitarian. Christian dogma of the Trinity posits that the Father, Son and the Holy Spirit are co-equal and co-eternal. The Bible speaks of the Son and the Spirit as errand boys of the Father; that's hardly co-equality. It's called suboridnaitonalist theology that is incompatible with the Trinitarian theology. It was actually taught by practically all early Christian apologists—until the first Nicene Council (325 AD).
Indeed the term "eternal" is something I do not use in reference to God because the term basically means time without end. Instead I use the term "timeless" because time is part of the Creation and not a property of or restriction on the Creator of it.
Very acute analysis Kosta, well done. As I’ve read the comments it seems that we are having trouble reconciling eternal beings using temporal understanding. I feel that the Trinity was a reaction to imposed monotheism (the Jewish understanding) and spiritual superiority to physical (the Greek understanding). Would you comment on that?