What is the test for giving notice of termination of a commercial tenancy?

The whole line of cases upon which this argument depends commences with Doe d. Pitcher v. Donovan (1809) 1 Taunt 555, 127 ER 949. In that case premises had been leased on a year-to-year tenancy with provision for termination on a quarter’s notice. Now the court held that notice expiring other than at the end of the year was not good, but as I read the judgment of Mansfield, C.J. it simply decides that the effect of the proviso as a term of notice was to reduce the usual length of notice from six months to three months, but that, in the absence of any other circumstances indicating the intention of the parties, the notice might be given at any time. The court held that the usual rule applied and that the notice must become effective at the end of the year. In other words, the court did not attempt to lay down any hard-and-fast rule but more or less said that in the circumstances of that case the notice was not effective.