I haven’t had a chance to document them all yet, but yes. Generally they are just repeating information that is already in the text in the Info tab so that you can see it at a glance.
means superseded. In other words, there was another Prediction or Training for the same message later on.
means repeated. In other words, there was an earlier Prediction or Training for the same message.
Normally, each message would only be processed once, so these are pointing out something that may be unexpected unless you manually told SpamSieve to reprocess a message.