Ferry passengers are warned to expect severe travel disruptions during a planned ferry strike later this week.
Further industrial action risks being a feature over the summer.
However, striking crews will work if the safety of the ship requires it at any time.
Seafarers in the union are to impose a work-
Shipping company Cal Mac warned the two day overtime ban would impact scheduled services.
Effectively, any ferry not operating to timetable could be hit.
On Friday, ships are liable to be stuck in port all day as RMT union members down tools.
Ferry passengers advised to rethink travel plans during industrial action
22 June 2015
Cal Mac said: “On June 26 a full day of strike action is planned which is likely to cause severe disruption.
“Passengers are advised to think about whether they need to travel on these days.
“Anyone buying tickets to travel during the period of this industrial action should be aware of the risk of potential disruption.
“If you have already bought a ticket for these dates and choose not to travel, we will give you a full refund or book you on an alternative sailing. If you choose to travel and your sailing is cancelled we will give you a full refund.
“We will also reimburse anyone who has to incur costs associated with unexpected accommodation or meals due to delays caused by industrial action.
“We are not however able to provide compensation for pre-