Not really Brendan.First, they will have had to have a big rise from the date of purchase to date.
And then the big fall would have to repeat itself.
Even with moderate price growth during the period when the property is held as a rental, a sell and rebuy approach would still produce a lower CGT liability.
I'm increasingly convinced that @Bronte's advice to "bank the CG and start again" is the right approach from a CGT perspective.