I can't speak for all girls, but I personally don't reply to texts unless we can do so within a minute or two.
Imagine if you text just before she goes in to a booking, an hour later she replies and you're with your Mrs who spots the message?
Better to lose out on a bit of business than ruin a relationship. It might be worth saying in your text that you're happy for her to reply as you use a punting phone, for example.
Or if she's happy to accept phone calls then all of the arrangements can be made within a few mins rather than back and forth
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