Ready for departure means times the majority of time consuming actions and checks which would delay an immediate departure have been completed. It was also reasonable for you announce that you were about to backtrack because in doing so your movement adds to the A/G station's knowledge of known traffic. But if you have any more conflict the next time you go flying you might want to tell the A/G operator about a marvellous little publication called
CAP 413. It's all about radio phraseology and if they look in Chapter 4, page 7 they'll see what "Ready for departure" means. But the bit that should really concern you when next fly from your airfield is Chapter 4, page 32 onwards - the section about Air/Ground radio.
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