Delete To Disc - Can you restore edit data or undelete Restore Edit Date

The advice on automatically writing changes to XMP is all appropriate and correct, but not quite complete: many aspects of an image's management and useful organisation within Lightroom, will not be included in what is written out to disk. Because they can only exist within a Catalog.

IMO it is a mistake anyway to presume a 1:1 correspondence of images withn LrC, and image files on disk.

For one thing, some image files may exist on disk that you didn't want included in the LrC Catalog (or that you deliberately removed before), and that work of selection would need to be done again if everything got re-imported regardless.

Also e.g. by means of Collection membership (which is not written to XMP) one image can behave organisationally as if it were many images, in the sense that it can be shown separately grouped with a lot of independent sets of other images. That "context intelligence" would be lost.

Furthermore if any virtual copies (or soft proofing copies) are made, sharing use of a given single image file on disk, there is no writing-out of the Develop edits etc for these EXTRA image versions. So if deleted out of the Catalog, that is not retrievable (except from some Catalog backup that was made while these extra image versions were still in place).

If you have set the option Automatically Write Changes Into XMP, then all your develop settings will be automatically saved in the photo's metadata (in raw .xmp sidecars or the non-raw files themselves). If you accidentally delete a photo from the catalog and disk, restore the photo and its .xmp sidecar (if it's raw) from the Trash / Recycle Bin and re-import it into the catalog.  All your develop settings will be restored.

"Will this info also be saved if I accidentally delte from disc in the future??"

You would need two things-

1) The camera files restored from trash or a backup location.

2) A saved Backup of the Catalog that contains the edit data. (You do backup the Catalog don't you??)

RESTORE PARTIAL from backup catalog?

As far as I am aware if you have multiple images selected and select delete from disk all data edit info from Lightroom will be deleted and unrecoverable. The original files should be in the trash/recycle bin along with the metadata that has been written to the file if that option has been selected.
I say “should” since I do not use the option to “automatically write to XMP” in my workflow.

Going forward, set the option Catalog Settings > Metadata > Automatically Write Changes Into XMP. Then all your develop settings will be saved in the photo's metadata (in raw .xmp sidecars or the non-raw files themselves).