This year, in all pre-1960 reckonings, there is no liturgically reckoned fifth Sunday and week of September due to the proximity of 29 September to the Kalends of October. The rationalist-literalist 1960 system considers 29 September to be the fifth Sunday, though the majority of the week to follow falls in October. How is this to be treated?
Unlike August in which its fifth week is a continuation of the same book from the fourth week, the fifth week of September contains readings at Mattins from its own book of the Old Testament, namely, Esther. The rubric given in an 1869 edition of the Breviarium Romanum states that when no place for the fifth week occurs, the following is to be observed:
1. The readings from Judith for the fourth week continue through Wednesday of this week inclusive.
2. On Thursday, the readings for the fifth Sunday (from Esther) are read instead of the Thursday of the fourth week's readings.
3. On Friday and Saturday, those from the Monday and Tuesday of the fifth week instead.
4. In cases of proper readings given for the first nocturne in any festal Offices on Thursday-Saturday of this week, the readings for the fifth Sunday are relegated to the first day of those three days in which there are no proper readings; then follows those of the Monday if the next day is free. If all three days have proper readings, then the fifth week is omitted entirely.
5. From Sunday, 29 September (actually, 30 September because of Michaelmas), the readings are from the first week of October and follow along that progression for the books of Maccabees.
This seems reasonable to the CTO if only for the sake of giving some exposure from each book of the annual cursus of Mattins' lessons rather than omitting entire books as would be the case in the 1960 rubrics.
In the USA and Canada, this Thursday is the Double II Class feast of the North American Martyrs; hence, proper readings occur in the first nocturne, so the lessons for the fifth Sunday of September are read on Friday, and those of the Monday on Saturday, while those of the Tuesday are omitted this year.