No, seriously; which transactions were reversed? I'm unaware of any such thing occurring on the network.

The construction of the network/consensus protocol means that Ripple would have to get a majority of all validators on the majority of everyone's UNLs to lie to reverse a transaction. Ripple likely does not have such influence /or/ if they do, then you are free to select a larger UNL set, along with the rest of the community, such that they /do not/.