In Catholicism, what is the proper order of the sacraments of initiation and what are the summary arguments in support of this order? In my parish in the diocese of Honolulu, we are in discussions regarding transitioning the catechetical process so that in a few years, the sacraments of initiation [Baptism, Confirmation, and then First Holy Communion] will be administered in their [that] proper order. My understanding is that some other dioceses are doing that as well.

Before it was Baptism, First Holy Communion [with First Confession], and then Confirmation.

The question is what should be the proper order of the sacraments of initiation with support from scripture and early Church practice, and how and why, if that was the proper order, was there a reordering from the proper order?

In this proper order, when is First Reconciliation/Penance/Confession?
Until about 30-40 years ago, here in Italy the order of the sacraments of initiation was Baptism, Confirmation, First Communion - and it's the canonical order, following the Cathechism. That order is still used when an adult recieve the Sacraments: notice that usually adult pepole recieve all three sacraments in the same day, so the order is not really imprtant.
But when in 1910 Pope Pio X established that the First Communion should be received from children at 7-8 years old, the Church encountered a problem: it's very difficult to explain to such young children what and who is the Holy Spirit, and all the meanings of the sacrament of Confirmation.
So, today, each italian bishop is free to choose the order, but most of them follow this:

Baptism
First Communion (usually at 8 years old)
Confirmation (usually at 13 years old, but some bishops prefer to wait until 16)

As said, they follow that order, having in mind what Pope Benedict XVI said in Sacramentum Caritatis

&quot;It must never be forgotten that our reception of Baptism and Confirmation is ordered to the Eucharist&quot;

About First Confession, it's usually celebrated few days before first Communion