What is the test for a motion for a continuance to retain counsel of a defendant's choice?

The right to effective assistance of counsel includes a right to retain counsel of one's own choosing. (People v. Courts (1985) 37 Cal.3d 784, 789.) A trial court generally should accommodate requests for a continuance to retain counsel of a defendant's choice if it can do so " 'consistent with effective judicial administration.' " (Id. at p. 791.) At the same time, trials must be heard and determined at the "earliest possible time" and continuances may be granted only for good cause because they "cause substantial hardship to victims and other witnesses." ( 1050, subd. (a).) A court's broad discretion to assess cause for delay must be exercised in a way that allows a defendant to prepare a response to charges, but it abuses its discretion and impairs the constitutional right to counsel only if the court insists on an expeditious trial in the face of a justifiable request for delay. (People v. Alexander (2010) 49 Cal.4th 846, 934-935, citing Morris v. Slappy (1983) 461 U.S. 1, 11-12 [75 L.Ed.2d 610, 620].)