I have never heard this in any liturgy, but if it is present in the original Latin text, the Church would understand it in a symbolic manner. Throughout Scripture symbolic periods of time are used with theological, but not necessarily historical, significance. For example, Scripture speaks of the “thousand year reign of Christ”. According to the Fathers of the Church, we, that is to say, all Catholics from the time of the apostles down to the present day, are living within the “thousand year reign of Christ”. Historically speaking, this “thousand year reign” has already been over 2000 years. The “thousand years” is taken symbolically and not literally…much of Scripture and the liturgy use poetical devices to convey theological truths. The sacred liturgy is not an engineering manual, but more of a divine love song.