I cannot answer your question exactly however as I worked in several Catholic relgious goods stores prior to entering the Poor Clares, ( One of our sisters was also a Benedictine Oblate prior to entering our community) this is what I would suggest:
I would suggest you call the abbey or a nearby Benedictine Monastery, and ask them how their Liturgy of the Hours differs from those published by either Catholic Book or Paulist Press. They would love to explain it to you in greater and perhaps more accurate detail than I am able to…
My (limited) understanding is that the Benedictines have slightly different formats for their offices mostly, because more parts are chanted. (simplified explanation of course) and that it can also vary from Abbey to Abbey. For instance the monks at Mt Angel in Oregon use a different version than the monks at Valyermo in Ca.
As for those published by Catholic Book or Paulist Press they are essentially the same and most (non Benedictine) communities would use those with adaptations for each order which are usually found in the ordo for that order.
I am not sure if this helps any? I am sure that there might be some Benedictines in the forums who will further clarify this for you…
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