The Leven amateur carded a five-under-par 66 at the Angus venue to record a three-shot win over professional duo John Henry and Chris Maclean.
“I really enjoyed Montrose,” said White, who had a spell in the paid ranks but now works for Cobra Golf after being reinstated as an amateur.
“It's only my second time playing the course after shooting 68 last year in the same event.”
He birdied the second, fourth, fifth and sixth before having to dig in on the back nine into a stiff breeze.
“After blasting my tee shot out of bounds on the last, I was pretty happy to get away with a bogey 5,” he added.
The circuit was set up by Alan Tait two years ago to provide playing opportunities in Scotland during the Covid pandemic.
“It's been great fun playing the tour over the last two years,” declared White, who had a successful spell at the University of Stirling.
“We've played some great courses and it's been a good opportunity for me to play with some of the pros who I work with”.
The win has earned White a narrow 2.5-point lead over Drumoig professional Jordan Brown in the order of merit, with The Renaissance Club’s Neil Henderson also to the fore.
Henderson shared top spot with Panmure’s Scott Grant in the previous event at Panmure, having triumphed outright for a third time this season before that at Spey Valley in Aviemore.
“I’ve been working on my long game with Pete Arnott and had a putting lesson with Gary Nicol and have holed loads ever since,” he said. “Spey Valley was great and is my favourite place to play in Scotland.”
The circuit’s visit to Duddingston produced a win for professional Fraser Moore as the Glenbervie man carded a three-under 69 at the Capital venue.
The 13th event of the campaign is underway at Ladybank before the final one takes place over the Lansdowne course at Blairgowrie.
The top six professionals and the top six amateurs on the order of merit will then progress to a grand final at Dumbarnie Links on 16 October.