UPDATE 1-Dixons Carphone reports 6 percent jump in Christmas revenue

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LONDON, Jan 22 (Reuters) - Britain's Dixons Carphone, battling a fall in profit and about to lose its top two directors, said on Monday it had enjoyed a solid Christmas trading period due to strong demand for the iPhone in Britain.

The electricals retailer tightened its full-year profit forecast range on Monday after posting a 6 percent rise in underlying group revenue in the 10 weeks to Jan. 6.

Dixons Carphone issued its trading statement a day earlier than planned after CEO Seb James said on Friday he would step down in April to join Boots, while the group's finance director Humphrey Singer is also due to leave this year.

The group said it had been helped by strong demand in Norway and Greece and an improving scene in its British mobile market due to the launch of Apple's iPhone X.

Dixons announced plans in December to reposition its mobile phone business after it reported a 60 percent slump in first-half profit, hurt by customers holding onto their handsets for longer.

It said on Monday its gross margins would continue to be challenged in the mobile sector, but the phasing of the iPhone launch and other new offers helped it increase its mobile revenue by 8 percent.

"For the remainder of this year we have an early Easter, a new Samsung phone and the first week or two of our World Cup promotion to look forward to, and work continues on redefining and refocusing our Carphone Warehouse business to be a simpler, less capital-intensive model," James said.

The group said it now expects to deliver 2017/18 profit before tax in the range of 365 million to 385 million pounds ($534 million). That compares with a previous forecast of 360 million to 400 million pounds given in December. ($1 = 0.7209 pounds) (Reporting by Kate Holton, editing by Louise Heavens)