From the Sailplane Racing Association's "The SRA Guide to Soaring
Competition", 2005 v 5.2 edition:

"If you decide to dump ballast, you must not do so in a thermal, unless
you are *certain* [original italicized] you are below all other
gliders: wetting down other pilots' wings is considered very bad form.
Be sure to know how long it takes to dump ballast, and start to do so
in plenty of time before landing."

I'd report the offending contest IDs to the CD, if nothing else.

~ted/2NO