sorry for saying TC prematurely… 
Using this
the newly created PDFs are being deleted instead of the webarchive source files…
Again, sorry for interrupting you again!
No worries!
As per my screen capture, do not Konvertieren & Fortfahren, only Konvertieren.
When you convert & continue the input has changed from the original webarchive to the PDF. This means the deletion applies to the PDF, not the webarchive.
yes, that’s done the job! Thanks again so much!
No problem.