The contract is frustrated, this is a legal term meaning it does not necessarily void the contract, but it is extremely unreasonable, as the delay is significant.
Accordingly, it would however be enough to terminate the contract, 2 weeks, it will be almost 3 months till you get the vehicle, so in that, it is more than reasonable for the contract to be terminated, or to organise some other arrangement between the parties.
Here is the legal definition of frustration:
Send them an email,
As the agreement was delivery of the vehicle in two weeks, the extended time frame to September is extremely unreasonable.
Accordingly, I hereby give notice to terminate the contract.
Any issues, contact consumer affairs
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