Re-inserting Images (imported from a mounted network drive)

When I need to change an image I have already inserted (without linking) and make the change in an external graphics package, deleting and reinserting the image does not normally change the display image, unless I actually change the filename.

Is there a simple way around this or to clear the relevant cache? Saving and reloading the document does not seem to refresh it, so it appears likely that the file is not reimported. I guess I could link all images in case they need changed, and then break all the links before sending elsewhere, but would appreciate a more straightforward approach.

For reference, I am using LibreOffice 4.3.3.2 in English (although the current document has been previously saved in German) and Writer. The OS is Ubuntu 14.10. However, I have noticed this effect in the past on different versions of LibreOffice and Ubuntu, but wanted to check it is a valid bug rather than misunderstood feature before filing accordingly.

Many thanks.

What exactly is the problem?

My understanding is that when you change and image, inserted without link in a Writer file, and do image processing using an external tool, you need to re-insert the image using a different file name. Please comment on my understanding.

Thanks for quick reply! That is correct. Actually, I have just realised the images I tested were imported from a mounted network drive (SMB), not local FS, which seems to be the issue: when I insert an image from the local ext4 filesystem, change the file in Inkscape, delete the image from Writer, and re-insert it, the change appears. When I do the same with the networked drive, it does not appear; should I file as a bug instead? Or perhaps it is intentional SMB timestamp caching by LO or GVFS?