I have a Hilchos Shabbos Shailoh.
Shabbos Morning after Kiddush, my hands and my Becher are wet from Grape Juice that I had just made Kiddush on.
I then stand up and walk to my sink with the Becher in my hand.
At this time I will rinse off my hands from Grape Juice so it will not be a Chatzitza when I wash for Challah.
The Shailah is, is it permitted to wash out my Becher (before I put it down on the counter) at the same time I rinse off my hands, or does this constitute Hachana being that I will not be using the Becher again until Havdalah.
As long as it is at all possible you may drink from it on Shabbos [for any drink], this would be permitted.
Shulchan Aruch 323:6 rules that drinking vessels may be washed the whole day, as drinking is common the whole day. The Mishna Brura  notes that if it is absolutely clear one will not be drinking the cup may not be washed.