Alternates!
The Germans had a mobile Alter-Met [only one] which turned up at the next base for TACEVAL. I am not sure how they knew, or whether they rushed it to the base being evaluated in time for Day Two.
It was fully mobile and, I seem to remember, had a trailer as well.
Being a Met Evaluator had its funny side, as when I asked the German S Met O what the wheels were for ................
Very difficult to assess: whereas the vehicle could not be in two places at once, neither could I. We never managed to run two TACEVALs simultaneously.