R. v. Mitchell, 2012 ONCA 804 is a useful case summarizing when an extension of time to appeal will be allowed:
 Before granting an extension of time, the court will consider: 1) whether the applicant had a bona fide intention to appeal within the prescribed appeal period; 2) the applicant’s explanation for the delay; and 3) the merits of the proposed appeal. Depending on the circumstances, other factors will include: whether the consequences of conviction are disproportionate to the penalty imposed; prejudice to the Crown; and whether the applicant has taken the benefit of the judgment. See: R. v. Price, 2010 ONCA 541, at paras. 19 and 20; R. v. Menear [2002} 162 C.C.C.(3d) 233. The list of factors is not closed. Other factors that inform the decision are the position of the defence at trial, whether the proceedings were consensual in nature and, more generally, whether the proceedings appeared to be fair and whether they were fair: R. v. Closs  O.J. No. 172 (C.A.); R. v. Kankis  281 C.C.C. (3d) 113 at paras 37-38. Overall, the court must consider whether the justice of the case requires that an extension of time be granted.