Back adjusting futures contracts or back adjusting for dividends / splits come to mind as I write this, but I would just reprocess these tasks from the raw data "as of date" if needed.
And actually, pricing can be revised as well, though it is much less common.
That said, versioning is not the only way to handle these kinds of things.
Versioning can also be useful as an audit trail for data transformation. Though again, these could be stored in another way as well.
There are however lots of time-series that do change in Finance, e.g. valuations, estimates, alt-data (an obvious one is weather predictions). The time-travel feature can being super useful outside of external data changing as well, as an audit-log, and as a way to see how your all-time evaluations have changed (say backtests).
You would use some convention for naming and parametrising backtests, 'different' backtests would get stored separately. But once you start updating backtests, running them in a loop with changing data, that's when the time-travel feature starts to be useful.
Also, hi James! :)