Tom Cruise and Katie Holmes
Last year's big celebrity split between Cruise and Holmes could set a trend for the rest of us in 2013 Reuters

Divorce courts are expecting an influx of business following the revelation that warring couples are most likely to register for a divorce on 7 January, which has been designated D-Day by the only group likely to win from the arrangements: lawyers.

Disgruntled spouses heading back into work will hardly be cheered by further findings from the profession. Tens of thousands of people are likely to find separation more costly this year, while the number forced to turn to "DIY" divorce kits is expected to surge.

One in five family lawyers surveyed by the accountancy firm Grant Thornton said more people were appearing in court without legal representation due to cuts in public funding. With legal aid cover to be removed from most divorce cases in April, that figure will rise further.

"This could put an even greater strain on an already stretched system, leading to longer delays in determinations and a detrimental impact on children," Liz Edwards, chair of the family lawyers' organisation Resolution, told the Independent. "While the reform of legal aid will help cut government spending, I am concerned that the social cost will be far greater in the long run."

More than 117,000 divorces were registered in England and Wales in 2011, down 1.7 per cent from 2010, when divorces increased for the first time in some years. More than a third of marriages are expected to end in divorce by their 20th anniversary.

From April, £350 million will be cut from the £2.2 billion legal-aid bill. State-funded legal advice will be limited to cases involving domestic abuse. Around 200,000 fewer cases - a 75 per cent reduction - will be eligible for legal help, according to the Government's own impact assessment.

However, consolation could be at hand. Possibly enticed by the findings, the website Illicit Encounters has designated 7 January the "most adulterous day of the year". The site, which described itself as the UK's "largest dating for married people" said the numbers seeking extra-marital relationships would peak today.

The site said the trend was partly explained by the prevalence of Seasonal Affective Disorder, with sufferers experiencing symptoms including lack of energy, withdrawal from friends and family, and a decreased sexual interest in their partner.