You should read the terms of your equipment lease. Usually the lease will allow an upgrade as substitution should the other model not be available. Your lease will answer your question. I wish you luck!
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In addition to Attorney Houghton's response, which I agree with, your lease will also have all of the terms related to breach of contract, termination of contract, and damage provisions. You may need to have an attorney represent you, if they decide to pursue this.
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the problem is that even if the lease did not allow them to upgrade you... if you paid for 6 months you may have waived the defense that you got the wrong machine.. otherwise the other attorneys are correct.. check you lease.
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