layout file changes get deleted overnight I've had a problem for a few weeks whereby any changes to a layout.html file get deleted overnight on a server. As a sanity check I just want to make sure there isn't anyway this can be done by Craft? (The updates have expired on the install, but surely this can't be the problem?)
Craft isn't doing that automatically.

Guessing you've got some automated deploy that happens at midnight or some such and it's overwriting manual changes?