The combined effect of section 66(2)(d) of the Migration Act and the associated regulations is that there is a strict (non-extendable) 21 day period in which an application for merits review can be lodged with the AAT. If an application is made outside of that time the AAT is without jurisdiction.
While that seems simple enough there are a number of Full Court cases where it has been argued that the refusal letter didn’t comply with 66(2)(d) and as a result, no proper notice had been given and time hadn’t started to run. The most recent of these cases is Singh v Minister for Immigration and Border Protection  FCAFC 31. Singh in turn considered two previous cases: DFQ17 v Minister for Immigration and Border Protection  FCAFC 64 and BMY18 v Minister for Home Affairs  FCAFC 189.
Section 66(2)(d)(ii) provides that the notice of decision must “state … the time in which the application for review may be made”. Although you wouldn’t think that would be difficult to comply with, in DFQ17 Perram J found that the information in the notification letter was complete, but it was held not to have been clear. Clarity was absent because the letter was found to be “piecemeal, entirely obscure and essentially incomprehensible”. A similar “letter not clear” finding was also made in BMY18.
Unfortunately for the appellant in Singh, the complaint about the format of the notification letter was held to be sufficiently clear and his appeal failed. However, while my experience is that refusal letters follow a template, it is worth checking whether or not they are “clear”. Of course the best way is always just to make sure you lodge your review application in time. If in doubt – do it earlier!.
Creative commons acknowledgment for the photograph.