Boomer for me the names are irrelevant.
The point is, if having two federal component states is the means for providing degrees of political autonomy in parts of Cyprus and equality at a federal level to the communites, then the problem is how to constuct means of insuring a federal system achieves this goal.
One approach would be that TC belong to one federal element (whatever its name) and GC to the other simply because they are either TC or GC, but my understanding is that this is not in accordance with EU prinicples.
The next option then is to say people in this area are members of one federal element and those in the other area the other, manipulating those areas to ensure a starting point at least of numerical dominance in each area / federal unit to each community. The problem with this is that to maintain such a system would require limits on which areas people could become resident it, or if it did not have such restirictions, then both federal elements could become numericaly dominated by the larger GC community, negating the whole point of a federal structure as a means to ensuring degrees of autonomy and political equality between the communites.
The Annan plan 'solution' to this was to adopt the second approach (federal state citizenship linked to geographical residency) and place temporary restrictions (upto 19 years) on right to residency beyond certain limits that increase over time upto the 19 years (or Turkish entry to the EU whichever sooner). Not ideal from either communites perspective but representing a compromise from both.
Not ideal from a TC perspective in that there is no guarantee after the temporary 19year period that both federal elements would not become numerical dominated by GC and thus in the process the TC community would loose the degrees of political autonomy and equality that the federal structure orignaly gave to them as a community. Not ideal from a GC perspective in that it placed limits for the first 19years on absolute and full exercise of individual rights to reside anywhere in CYprus.