When is wud.watch.digest really enabled?

[gbcreation]

In the Labels documentation, it is specified that the default value for the wud.watch.digest label is false when this label is missing.

But at the end of the Variables section, there is a red callout indicating this:

By default, WUD enables it only for non semver image tags.

("it" being "digests watching")

This sentence is confusing. Does it mean that:

• if the wud.watch.digest label is not specified, WUD will enable it if the image tag is not a valid semver?
• what's the behavior when the wud.watch.digest label is specified?
  • is digests watching used when the image tag is not a valid semver, even if wud.watch.digest is false?
  • is digests watching not used when image tag is a valid semver, even if wud.watch.digest is true?