When does the “3 years” start for the purposes of s.68(6) MHA?

What happened with your patient in the end?

When writing the question in Six-month reference and notional s37 patients today I nearly added the following paragraph, but then I remembered this topic and realised it belongs better here. It seems to be almost the same legal question as yours but applied to a different factual scenario.

If a patient was originally transferred under s47/49 and that changed to notional s37, when would the three-year period commence? Jones (25th edn, 1-933) says it’s the date of the notional s37. That makes some sense as s68 doesn’t apply at all while the patient is restricted (sched 1 Part 2). But I wonder whether the wording of s68(6) would mean that “since his case was last considered by such a tribunal” really goes back to the s47/49 date.

What do you think?