A small team of designers and editors is understood to have produced a fresh dummy of the Sun on Sunday, with more editorial and sales staff working on the project as News International gets closer to committing to a launch next year.
It is thought that work on a new dummy version of the title to replace the News of the World, which was shut in July as hacking allegations engulfed News International, began again in the past month.
Development is understood to have been hastily shelved in the summer after James Murdoch, the executive chairman of News International, told a committee of MPs that the publisher had "no immediate plans" for a launch.
The Sun's editorial staff is also understood to have swelled by as many as 60, following the closure of News of the World. This is being interpreted as News International putting former NoW staff in holding roles at the weekday title until a decision is made on whether to launch a new Sunday paper.
Speculation has been fuelled by the fact that a number of the staff are in roles that seem to almost duplicate existing positions, although different job titles are being used, as well as the Sun's apparently top-heavy editorial management structure.
Lisa Collins – who left the Daily Mail in April having run the life and style pages, and previously edited Femail – has joined a Sun editorial management structure that includes editor Dominic Mohan and number three and Saturday editor Victoria Newton.
The top-heavy structure has led insiders to speculate that Newton, the former deputy editor of the News of the World, will take charge of the Sun on Sunday, Mohan will edit the Sun from Monday to Friday, and Collins will take the reins on the Saturday edition.
Several sources believe that the Sun on Sunday launch date has been pushed back to late January or early February.
A green light is still not certain after the arrival of Tom Mockridge, the former chief executive of Sky Italia parachuted in to run News International when the hacking scandal hit in the summer.
"Before Mockridge arrived there was most certainly an advanced plan although there was no exact start date on it," said one source with knowledge of the plans.
News International is also thought to have hired about 40 retail sales staff, an indicator that it is laying the groundwork to get the Sun on Sunday the reach that it will need to mount a successful return to the market.
"It is considered to be an inevitability as far as looking at it commercially; the cost of investment in print plants means they need to have another paper on a Sunday," said a second source.
"[News International's] commercial side is not in it in a major way yet and I don't expect they will be given a lot of notice, they'll be lucky to come to agencies more than a couple of weeks before launch in my opinion," added the source. "Advance warning to the market would just tip off competitors and give them time to come back on cover price, marketing, promotions or even 'Hackgate' exposés to undermine them."
However, the source believed that a return to the market would be supported by advertisers. From a purely pragmatic point of view about a quarter of Sunday newspaper sales disappeared at a stroke with the closure of NoW and a new launch would see rivals lose sales and provide more reach for advertisers to book campaigns.
"The market would find money to book, it would not be maximising client spend if it didn't," the source added.
In September News International announced the creation of a new "digital journalism company" with 19 editorial roles – seven in sport, seven in showbiz, three in multimedia and two in production – that has been claimed to be an attempt to take on a slice of the market exploited by Mail Online.
While this may explain some of the retention of former NoW staff, a number of observers believe that the initiative is also useful to take some of the focus off the potential new tabloid launch.
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