CT Plus is warning that roadworks and temporary one ways in areas of St Peter Port will cause timetable disruption.
The bus operator has published a map on its Facebook page showing extensive roadworks scheduled for next week, beginning on Monday 7 November.
It says the pinch point is the Couture, Collings Road area shown at the top centre of the map.
Here, several roads are either closed or one ways are being introduced, covering an area between St Jacques and La Vrangue.
CT Plus says it will push traffic into the Grand Bouet causing a knock on effect along Les Banques.
Traffic and Highways declined to comment.
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