Thank you. If she was going to cancel, as she is intending to, she must show that you had genuinely acted in breach of contract, serious enough to make the whole contract void. Minor breaches will not qualify, although it is for a court to decide what is serious enough in the circumstances.
When you provided the quote you specifically said that “1st draft drawings will take 1-2 weeks”. You did however advise the customer that you were behind on work and this timeline may be extended slightly, although no specific timeline was agreed. At that point the customer would have had the opportunity to get back to you and say that she is not happy with the delay and to cancel as a result. She would have had the right to cancel then if needed. On the assumption that she did not challenge the delay and did not say anything else, it would be assumed that she had accepted there would be a slight delay and therefore cancelling on those grounds alone would be a bit difficult. Of course, that does not mean you can take as long as you want and you still have a duty under consumer laws to provide the designs within a reasonable period of time. If you initially promised 1–2 weeks, a reasonable delay would be perhaps 3-4 weeks. Any longer than that, getting into 5-6 weeks or more, would unlikely be reasonable and would again allow her to consider cancelling.
Just to point out, her letter does correctly refer to there being no drawings within 1-2 weeks as promised, she does not state she is cancelling because no plans were provided. Therefore, if you are now 3-4 weeks in and have still not provided any drawings, you either have to do this without further delay, or consider allowing her to cancel and reimbursing her the fees paid, less anything she has already received a benefit from.
Refusing to do this could allow her to go to court to challenge you over this, although as it is only £750 it will go to the small claims court and the risks are relatively low, even if you lost.
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