I am not an attorney and cannot offer legal advice. My response is based on reading the Private Ways Statute (PWS) and my experience as President/Road Commissioner of our statutory road association. Therefore, I advise you to check with qualified experts before acting.
The PWS, 23 M. R. S. §§3101-3104, offers a means for people living on a private gravel road to form and administer a road association in which road maintenance and related costs are shared fairly and equitably by all property owners along said road. Selections from the following 3 subsections of Section 3101 state: (italics are mine)
2. When 4 or more parcels of land are benefited by a private road, private way, or bridge as an easement or by fee ownership of the private road, private way or bridge, the owners of any 3 or more of the parcels, as long as at least 3 of the parcels are owned by different persons, may make written application to a notary public to call a meeting. … Copies of the warrant or similar written notice must be mailed by means of the United States Postal Service to the owners of all the parcels benefited by the private road, …
4-A. A road association under this subchapter through its commissioner or board may address present and future repair and maintenance of a private road, private way or bridge as authorized by the owners at meetings called and conducted pursuant to this section until the association is dissolved by a majority vote of its members.
5. By a majority vote of the owners present and voting in person or by written proxy or absentee ballot, the owners may determine what repairs and maintenance are necessary and the materials to be furnished or amount of money to be paid by each owner for repairs and maintenance and may determine the amount of money to be paid by each owner for other costs, including, but not limited to, the cost of liability insurance for the officers, directors and owners and costs of administration.
I do not believe two road associations on the same private road are possible under the PWS.
According to my reading of the above subsections, if three owners in the subdivision section along your common private road choose to form a statutory road association according to the steps indicated in the PWS then you and other owners in the non-subdivision section will receive notice at least 30 days in advance of the proposed meeting. All owners along your road present and voting in person or by proxy or absentee ballot will determine by majority vote if the statutory road association is approved or disapproved.
It would not be possible for you to avoid joining the new statutory association if approved by the majority of owners on your private road. Unless there is a significant divide in the vision of how to achieve satisfactory road maintenance between your two groups, you may find working together, distributing the costs fairly and equitably among all owners, actually lowers costs per owner and improves your road. Also, you may be able to settle on a lower share of maintenance fees because you live at the beginning of the road. Owners on our road have continued to support our statutory road association since its beginning in 2016 and we now have effective means to enforce payment of maintenance fees in delinquency.