I had a leak in the curbside storage compartment area of my 2018 Globetrotter. I posted the following link as to what I felt the problem was. I was wrong.
It took another 4 months to figure out but, the problem was the grommet for the electric wire that provides power for the Zip Dee awning. When the work was done in that area for the frame separation issue, that grommet had to be removed and it was apparently not put back in all the way. It eventually worked its way loose and allowed water to intrude the area. This led to part of the subfloor to be compromised. All of this was repaired under warranty recently. Henry McKnight, of the SC Coastal Airstream unit, diagnosed this for me at the Canopener rally in January.
The grommet was put back in properly by JC and then sealant was added around the grommet as an additional prevention.
At the Canopener rally, I showed a fellow Globetrotter owner the issue and his grommets were installed properly. Fast forward to today. That owner recently had some awning work done at Jackson Center where the awning arms had to be removed. He called me today and the same grommet that was installed properly in January is now loose. It appears it was not installed back correctly as well.
My suggestion is if you have any work done on your Airstream in that area, (it does not have to be awning work), I would check to make sure the grommet that supplies power to your awning is pushed in far enough for seat in the horizontal slit of the grommet. From experience, if that grommet is not seated properly, water will run off the awning, down that rivet seam in into the hole where that grommet sits. It will then penetrate to the subfloor and rot it out if you have a plywood subfloor.
If you have a FB twin, you may see water in the storage compartment as well. That water will, however make its way to the subfloor.
If this happens on the road, I would suggest 1) keeping the front of your Airstream elevated when camping so that water will run off the back of the awning 2) use some duct tape and make a tent around that wire so that water will not enter that area.