So far, just calling releases 1, 2, 3, etc. seems to be the most
straightforward. For maintenance releases, 1.0, 1.1, 1.2, etc.
The /etc/ast/sources.list, use 1, 2, 3 etc. It will automatically
accept maintenance releases of the major release.
Perhaps the names could be devuan1, devuan2, etc. People making
devuan derivatives could simply replace 'devuan' by their
derivatie name. This might enable people to refer to ours and others
unambiguously if they choose.
But the proposal that seems most fun is to use the names of ancient
cultures and archaeologica sites. Or maybe even geological eras.