Did they indicate what was being fixed with the repair kit?
They did say that the "fix" was to elevate the drain.
I believe they meant elevate the VENT.........
because when experiencing the problem I discovered that although the grey tank was almost empty, an amount of water came out the vent while I was trying to force the water down the shower drain.
This led to my idea that the angle of the Agile was causing water to block the vent, so I repositioned the Agile so the front was slightly ( and I do mean slightly) higher than the back.
The standing water in the shower drained immediately, which indicated to me that where the water had leaked near the front of the tank was where a vent was located and the theory of blocked vent may have been correct. On our forthcoming trip, I am taking a length of flex. tubing and if the drain plugs, will insert the tubing into the drain to introduce air into the system.
A dealer has ordered the repair kit for me and will install it on our return.