Tune them in isolation, have both loaded and then you’re set!
Had Sydney tuned on the Monday, travelled to Mt Fairy overnight, then Tuesday drove north to Lithgow via Oberon through Goulburn - had ABC CBR & SYD side by side for much of the high spots near the Lachlan valley.
This is exactly how DAB+ should be, bettering FM for metro, if only ACMA could get the planning right.
With 2GN the culprit. They will scream for a freq swap as per ABC submission in no time.