Cirrus 920 bath sink issues

Don't think there are many Cirrus owners here, curious I did a search and only found reference about the sink issue on a face book group
https://www.facebook.com/groups/1537597943207839/
Did find a lengthy review of a couple that full time in a cirrus mentioning the sink issue ( and the face book group).
https://www.truckcamperadventure.com/living-in-a-cirrus-820-the-good-the-bad-and-the-unexpected/

I'll cut out of context
"...Have you had any problems with the camper?...

Lonnie: Only a few. One of the major design flaws is the fold-up bathroom sink. We appreciate the idea behind a fold-up sink, but the sink does not drain properly, sometimes not at all. If there is a bit of water left in the bowl and you fold it up, the water leaks out of the bottom, all over the place. It’s a mess. There’s a Facebook group for Cirrus owners and we all have the same issue. One brave soul took his sink off of the wall to investigate, finding very insufficient plumbing. First, there is no P-trap. On top of that, the drain line measures just 3/4-inch and drains upward. It’s no wonder it doesn’t work! Our next major project is to re-do the bathroom, starting with ripping out that sink and opting for a small corner sink..."



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Ford

F250 4x4 DRW Diesel, 01 Elkhorn 9U

Our camper projects page

We have a model 820 that we bought used and have owned for less than a year. We have camped in it about 30 nights. We have never noticed a problem with the sink. Maybe, it needs a few seconds to drain after using before being folded up?