“On a motion to extend the time to appeal, the overriding principle is whether the justice of the case warrants an extension. Relevant considerations include whether the party requesting the extension formed an intention to appeal within the relevant time period, the length of and explanation for the delay, prejudice to the responding party arising from the delay, and the merits of the proposed appeal: Enbridge Gas Distribution Inc. v. Froese, 2013 ONCA 131, 114 O.R. (3d) 636, at para. 15.”