It seems pretty obvious—start the procedure turn (PT) past the “remain within” fix and don’t exceed the specified distance. But, there are other considerations such as having enough time and distance to make the FAF altitude inbound.
Then, there’s the Buchannan Field VOR Runway 19R approach at Concord, CA (KCCR). Here, the chart clearly shows that the procedure turn begins after HUKVI. Or does it?