An MHK has queried whether new bus timetables will be needed if new 20mph zones are brought in around the Island.
Onchan's Rob Callister has written to Infrastructure Minister Michelle Haywood about the issue.
He says slowing down buses could add between 10 and 15 minutes to journeys through his constituency.
And he's called for clarity, saying the Department of Infrastructure previously said it wouldn't affect timetables.
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