Extension of time in the face of solicitor error

Precision Contractors Ltd v Government of Saskatchewan, 2012 SKCA 96 has a useful passage regarding solicitor error:

 [4] The leading case authority concerning the extension of time in the face of solicitor error is that of Bank of Nova Scotia v. Saskatoon Salvage Company (1954) Limited (1983), 29 Sask. R. 285 (Sask. C.A.). The Court there held that solicitor error may provide the basis for an extension of time if the extension does not result in serious prejudice to the other party, noting that other factors also fall to be considered. These consist of whether the appellant (i) had a bona fide intention to appeal within the time limited for appeal; (ii) has an arguable case; and (iii) acted with reasonable diligence or has a reasonable excuse for the delay.