The text in section "4.2. Version Numbering" http://www.openehr.org/releases/AM/latest/docs/Identification/Identification.html#_version_numbering
..is confusingly ordered and described...
"This leads to identifiers such as:
1.3.5-rc.3 # release candidate for version 1.3.5, build id 3
1.3.5-alpha # alpha development version based on version 1.3.5
Should not 1.3.5-alpha rather be based on 1.3.4 and be planned to later (optionally via 1.3.5-rc) lead up to an upcoming 1.3.5? Thus it can not be based on 1.3.5...
This reasoning seems to be supported by what the text further down in the spec indicates "the minus sign (-) is understood as indicating a version that is 'less than' the target version 1.3.5, i.e. 1.3.5-rc.1 is an interim version leading to the stable version 1.3.5."
Also, the "instance_uid_slice" in the lexical definition above the examples seems wrong, why would it need to be "5 or more digits"?
Also the dot between version_modifier and instance_uid_slice is missing in the lexical definition (as exemplified in "rc.3")
Some inspiration for examples could be borrowed from https://github.com/regionostergotland/openehr_definitions/blob/master/README.md (but don't copy the unorthodox "alpha" part without modifying it to follow spec)