DFDS said the additional dates would be 6 and 20 July and 3, 17 and 24 August.
The operator said it would add an extra sailing on 2 July in response to demand from passengers travelling to the Le Mans 24 hour classic motorsport event in France.
DFDS added that despite withdrawing the plans it remained open to further discussions about future inter-island connectivity and believed there was value in improving links between the islands.
