Then we better rephrase:
If the winner of the challenge does not respond to the notification of their success within 24 hours, an Open house can be declared when there is consensus between multiple other posters which are on line.
Likewise might be added:
When the poster of a challenge does not respond within 24 hours of a posted answer, this poster can be declared winner if the answer is considered correct in a consensus of multiple other posters.
I personnally try to give indication ahead when I might not be able to answer.
Or indicate OH in advance when correct.
My chance will come another time.
I would like to emphasise that I really like the challenges with multiple photos or clues.
I also value the remarks of other posters on the same airfield or the comparison between then and now.
In that regard Jenkins saved the day at Koffiefontein!
All the best for 2019!
SLB