DB6, what's wrong with turning downwind before you reach 1000'?
I teach my students the "picture" of when to turn downwind - i.e. when the tailplane just starts to cross the runway extended centre-line. I then show them how this picture only works in level flight, and that if it is necessary to turn downwind before reaching 1000' (whether for the reason you give, or an early turn onto cross-wind, or a strong wind from the dead side, or any other reason) there is a different picture to be learnt, with the tail-plane a little past the extended centre-line. Doesn't seem to cause too much confusion for my students.....
FFF
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