The New Oath Liturgies of Battle, given to Chaplains in Rites of Battle says it follows the rules of oath taking in the core rulebook, if that is the case isn't it supposed to have a few attack/defence patterns to go along with it or am I missing something, or is its effect an add on to whatever oath is available to the Chaplain's base specialisation?

The squad mode abilities were not listed in Rites of Battle when it was published.

The Squad Mode abilities available to a Chaplain under the Liturgies of Battle Oath are as follows: Furious Charge, Squad Advance, Soak Fire.

As confirmed by FFG.

Many thanks for passing the information on Herichimo, you're a star.