So the Pope made a change in the Holy Thursday rite of Washing of Feet and both Progressive and Traditionalist Catholics tend to see it as a harbinger of change in the Church. They only disagree over whether it is a good or a bad thing. I think the assumption that this signifies change to areas of doctrine is false. I think that people are forgetting a few things, and forgetting these things lead to bad conclusions.
The point I would make is that when Our Lord acts, there is a great deal of depth to His actions. It would be foolish of us to limit the meaning of His actions to only one aspect. So the Church can decide to emphasize one aspect of this depth of meaning at one time in her history and another aspect at a different time. In doing this, the Church is not contradicting the other aspects of meaning.