Thanks for your questions. I have answered most of these in other articles so I ask that you read some of those for more comprehensive answers. The labels I add at the bottom of this article should lead you to further material pertinent to your questions. First of all, while the implementation of c 603 has become greater over the past 41 years, it has not become entrenched if that implies it is more valid now than it was when it was first promulgated in 1983. As I am sure you will understand, having a canon law that allows for consecrated solitary hermits, does not mean that every person that applies should be automatically consecrated. Moreover, having such a law means dioceses need to learn more about the vocation, appropriate candidates, or the varied forms of solitude that exist apart from eremitical solitude, and other things as well if they are to implement c 603 in their diocese. As I have written for more than a decade and a half, c 603 involves both dioceses and candidates in a fairly steep learning curve. Even so, c 603 has been the norm for eremitical life, and especially solitary eremitical life, from the day it was promulgated.
This also means, however, that it is an added form of eremitical life; it does not supplant earlier forms of life that are non-canonical or lived in the lay state (the baptized state). If you should desire to continue living eremitical life in this way, you are certainly welcome to do that. As a baptized Catholic, you are free to do that. If you want, you can (and I believe you should) use c 603.1 as a guide and norm for the nature of that life, but c 603.2 will not apply to you. (If you write a Rule of Life, don't expect it to be approved by your Bishop and diocese, but doing this is extremely helpful in living a healthy and faithful eremitical life. You can certainly have your spiritual director read it and help you live it.) If this is your choice, you will not be a consecrated hermit nor someone living eremitical life in the name of the Church, but you will still be living a life according to your baptismal consecration that is an exemplar for others in the Church.If you decide to petition for profession and consecration under c 603, and assuming that you are canonically free to do so, then yes, you will need to go through a discernment and formation process. Remember that you are not merely seeking to be "approved" by a diocesan bishop, but instead, you are petitioning to be initiated into the consecrated state of life which requires public profession and a second consecration. Just as people petition (seek, postulare) admission to religious life and profession and consecration therein, you will be doing the same with solitary eremitical life. It takes time, and so it should!! You must understand the canon, have a vision of your life that is consonant with that, write a Rule that demonstrates how you will embody this canon and the Gospel of Jesus Christ, etc. All of that takes time and formation, even if you have lived as a non-canonical or lay hermit for 15 years. If the diocesan staff discern that you are a good candidate for consecration under c 603, they will approve you for a mutual discernment and formation process. This does not mean you will be admitted to profession and consecration, but it is a good step toward that.
The diocese cannot simply "approve you" in a way that makes you a c 603 hermit any more than a religious can merely transfer to c 603 standing. You must be prepared for profession and consecration because the consecrated state is different than the lay state. It is never about merely signing a piece of paper (though there are certainly a few of those you will have to sign before your perpetual profession!). Instead, one will need to be created a canon 603 hermit by making public profession(s) and accepting the canonical obligations associated with this life. Consecration is part of the rite of perpetual profession.After some posts from the past couple of months, let me assure you that the non-canonical or lay hermit vocation still exists in the Church and is something I believe has a greater representation than c 603. I believe, as I have said many times, there will always be more hermits in the lay or non-canonical state than there will be in the consecrated state. Let me also assure you that being "non-canonical" does NOT mean being illegal. It simply means not bound by the canons that bind consecrated ("canonical") hermits. One does remain bound by the canons applying to the laity so in that sense one is bound by canon law. Some hermits live their lives under c 603 and other canons additional to those binding a lay person. We call those hermits "canonical". Others live their lives without additional canons; we call those non-canonical. Both are legal in differing ways. Oh, one final point on something I mentioned above, namely canonical freedom: if you have been married, and if you have been divorced but without getting a decree of nullity, then you are not free canonically to take on another canonical or "life vocation". (If, on the other hand, your spouse has died, then yes, you are likely canonically free to try for c 603 standing.) Your diocese will tell you this when they see your Sacramental record.
I'm sorry to reiterate all of this, but your questions are reminiscent of someone who has heard or espoused the opposite of a lot of this, so I wanted to be sure and spell it out again. The information on living as a hermit in the non-canonical or lay state is particularly important because it is important to understand that eremitical life can be lived in lay, consecrated and clerical states. As lay persons, we are free to live very many vocational paths, but if we want to do so in the consecrated state or do whatever it is in the name of the Church, the Church must discern and form us (or make sure we are adequately formed) in the vocation herself and then admit us to profession and consecration. Please note that neither have I been making any of this up since beginning this blog in 2007. I am merely exploring what the Church established the moment she promulgated c 603 in 1983. Your questions help me do that as so many others have done since my own eremitical consecration under this canon in 2007. Whichever choice you make, you are in for an adventure!! May God bless your eremitical life!