The comms plan can refer to the individual plan if necessary, instead of repeating the information. Some projects won't have a schedule plan (in the real world) so having that information in the comms plan makes sense as it won't be elsewhere.
I have realized that some of the management plans, like schedule or cost, establish the reporting format, which is defined as the "format and frequency" for the reports to be shared. I wonder if there is here certain overlap with the communication management plan, as this also contains the frequency for the informations to be shared.
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