Dimension reverting to that of an earlier version of a model - seen this?

In this instance hole dimensions on sketch / feature in fully finished, drawn and issued model have reverted to values from an earlier version of the model.

Images show two different instances of the same model, one with correct dims and one with reverted values.

This is an example issue, however we have seen other examples e.g. a datum plane that, after several weeks of work and numerous regenerations would randomly revert to an earlier angle dimension value. It would do this sporadically / randomly across multiple users and machines. Anyone seen similar?

Thank you.

P. Lane

SolidworksParts And Features