2 thingz. . . . .
1) This is exactly why I will only book over-the-water flights with a GUC when I know in advance that the GUC UGs are available immediately. I realize that not everyone has the flexibility to do that.
2) I'm fairly sure, knowing KLM as well as I do, that they didn't say "GF yourself". Their boilerplate line is. . . ..
"I'm sorry sir, but that is NOT POSSIBLE!"