Whilst I have not had personal experience of having my DSRs trashed by non-working apps  or smartphones as reported by other sellers, I do think the DSRs are the problem area that ebay needs to concentrate on.

Sellers who are frustrated by not being able to neg buyers should simply take a deep breath and not post any feedback whatsoever.

A seller has the option to respond to unfair feedback and a calm explanatory reply does more to reassure potential buyers than a vent.

Changing Postage Time to Dispatch Time as mentioned on another thread would clarify the system for buyers.  However if the DSRs are being trashed unintentionally because of technology glitches, this is damaging to good sellers.