The giant oil rig which has been lighting up the Belfast night sky all winter will be staying in the city until next month.
The 360ft Blackford Dolphin, which sailed into the Harland & Wolff shipyard in early December from Brazil for a 60-day refit, is now set to leave in April, following the completion of additional "emergent" work.
Harland & Wolff said the initial work schedule was finished within the specified time frame, but following inspection, the owners decided that extra structural work was required.
Over the festive period, the rig acted as the city's unofficial Christmas tree, bedecked with lights, and is so large, it required the relocation of the landmark yellow Samson and Goliath gantry cranes. David McVeigh, head of sales and marketing at Harland & Wolff, said that while a 'plan B' for the cranes may be required if the work continued into the summer, the workers were delighted with the extension of work.
Some 600 skilled tradesmen, including welders, electricians, painters and engineers have been recruited, with around a third of the temporary workers sourced from Northern Ireland
"Some of the guys have been working 12-hour shifts, seven days a week, some have been working all over the Christmas period, and some of them will be delighted with the prospect of a bit of extra work," added Mr McVeigh.
"With the gantry cranes, they will definitely be required soon, as there is some very large equipment on the other side of the dock which we need to deliver to customers in the summer. If for some reason the work goes on for longer than anticipated, we will need to come up with a 'plan B' but in engineering, there is always a 'plan B!'"
Aberdeen-based Dolphin Drilling Ltd awarded the contract – worth tens of millions of pounds – to Harland & Wolff for the dry-docking of the rig in August 2013. Around 1.2m tonnes of water had to removed from the longest dock in the world to accommodate the rig, which has a rated water depth of 7,000ft and a drilling depth of 30,000 ft.
Originally built in 1974 in Norway, it has been upgraded and repaired in the firm's 556m x 93m main building dock before heading out to the North Sea.
The Aker H-3 model rig underwent a major upgrade from 2006 to 2008, when Harland & Wolff designed and built accommodation blocks and other features.