Don't know Stappleford at all, but I know that first solos at White Waltham are banned on 07. I assume it's because of the rather strangely-shaped published circuit, which calls for a turn onto 010 as soon as safe, followed shortly afterwards by a turn to 340 for the cross-wind leg.
The only thing I can say is that these things happens - aviation is full of delays, and you'd better get used to them. But don't worry - your day will come, and will be even better for having to wait for it!
FFF
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