Theory On Lancelot's whereabouts during the timeskip (Percival Revived)
It's obvious that he might still be in Benwick (possibly training or still hunched up in his room), but after Percival assisted King & Nasiens on defeating the last peril knight, it's likely that word got out on the knight's defeat & Percival coming back to life meaning that somehow in someway Lancelot could easily get word on this information & left Benwick immediately to find Percival (there might be a chance where he meets up with everyone at the tournament or so- because to me it seems like that's what its starting to build up at).