Article 17 of the Excise Tax Executive Regulation, issued by Cabinet Decision No. 37 of 2017, fixes the length of the Tax Period. The Tax Period is the Gregorian month. Upon the Registration of a Taxable Person, the Authority may direct that the first Tax Period be longer than that standard period. As an exception, the Authority may also direct a Taxable Person to submit Tax Returns by reference to a longer period, or approve his request to do so, and such a request must be made in the form and manner it directs.