This reminds me of a time, in a previous life, (2003-2006) when I had a part time job delivering demonstrator cars, primarily Renault, out of the Southampton docks.
We'd turn up at 6am for a long run and go out with 5 cars with one car being used as a taxi until the last car had been dropped off and other cars had been picked up. Then the taxi car would be dropped off and one of the others would take the "Taxi" driver to his pick up car and all head back to Southampton.
This particular morning we were in 5 Renault Senics heading for garages and companies in Wales. It was a couple of degrees above freezing when we left the docks but soon dropped below and by the time we got onto the M4 at about 0730 it was a hard frost.
We'd all done the checks beore leaving the docks an that included washer fluid. By the time we were on the M4 all the cars spray nozzles bar one had frozen up and the salt on the motorway made it night impossible to see out of the windscreen so we each took it in turn driving behind the lead car, who must have had proper screenwash instead of our water, and he sprayed his washersover each of us in turn, with each of us catching a small amount of overspray, giving enough visibility for us to continue. Just one of some crazy stories from that time.