in early of March vs on early of March

Some examples from the web:

• It was early in the morning of March 24th when the Genji and Heike clans fought their last sea battle.
• As regards Agenda 2000, in spite of the agreement reached in the early hours of 26 March, the image portrayed by the Heads of State and Government was one of confrontation and a lack of vision for the future.
• whereas in the early hours of 25 March the police brutally stormed the tent camp set up by young people and students in the centre of Minsk and arrested hundreds of protesters,
• whereas in the early hours of 25 March 2006 the police brutally stormed the tent camp set up by young people and students in the centre of Minsk and arrested hundreds of protesters,
• whereas in the early hours of 25 March the police brutally stormed the tent camp set up by the opposition forces in the centre of Minsk and arrested hundreds of protesters,
• Those measures expired in early March 2003.
• A snowstorm and high winds left over 220000 homes without power for more than 48 hours in early March 2010.
• The Commissioner for International Cooperation, Humanitarian Aid and Crisis Response visited Haiti in early March.
• It sheds its leaves in early March.
• The monetary data for January 1999 which were released in early March 1999 showed a substantial further increase in overnight deposits.
• To contain exchange rate volatility and excessive market pressures, in early March 2007 Národná banka Slovenska intervened to weaken the currency.
• I visited Zagreb in early March and found that Croatia's European vocation was strong enough to settle this problem if it was hampering the accession negotiations.
• The common website that the Commission is running went live back in early March.
• A specific audit for the above mentioned project is foreseen, and is expected to commence in early March 2004.
• At the unofficial Council meeting of the Ministers for Education in early March, the Minister representing the Presidency put forward the idea of a common history textbook for use in all Member States.
• In early March, the Egyptian Government is organising an international conference in Sharm el-Sheikh in support of the Palestinian economy for the reconstruction of Gaza.
• Compliance with minimum standards during the coming local elections in early March would be a second step, followed by a convincing commitment to fulfil all the conditions outlined in Parliament's draft resolution.
• A change in the law in early March 2010 meant that those erased people who had previously been unable to regularise their residence status could now do so; the deadline is three years hence.
• Nguyen Van Dai is one of two Christian lawyers arrested in early March, facing several accusations relating to his defence of religious freedom, including disseminating 'alleged infractions of religious liberty'.
• A seventh member of the group was arrested in early March, after being summoned to the offices of the Intelligence Ministry.

Some examples from the web:

• Those measures expired in early March 2003.
• A snowstorm and high winds left over 220000 homes without power for more than 48 hours in early March 2010.
• The Commissioner for International Cooperation, Humanitarian Aid and Crisis Response visited Haiti in early March.
• It sheds its leaves in early March.
• Between early March and the end of October the euro appreciated by almost 19 %.
• The monetary data for January 1999 which were released in early March 1999 showed a substantial further increase in overnight deposits.
• To contain exchange rate volatility and excessive market pressures, in early March 2007 Národná banka Slovenska intervened to weaken the currency.
• Moreover, by early March, implied volatility surged on all major stock markets, probably signalling a significant reassessment of stock market risks.
• I visited Zagreb in early March and found that Croatia's European vocation was strong enough to settle this problem if it was hampering the accession negotiations.
• These perspectives will, hopefully, also be addressed with due seriousness at the UN meeting scheduled for early March.
• The revised electronic standard templates will be sent to all Member States at the latest by early March of the concerned year.
• The common website that the Commission is running went live back in early March.
• A specific audit for the above mentioned project is foreseen, and is expected to commence in early March 2004.
• As I speak to you now - it is early March - it is really too early for me to announce that end date.
• At the unofficial Council meeting of the Ministers for Education in early March, the Minister representing the Presidency put forward the idea of a common history textbook for use in all Member States.
• Net inflows were very strong in the first half of the year, notwithstanding a shortlived episode of financial market turbulence in late February and early March.
• First, long-term bond yields fell in late February and early March, following a pronounced decline in risk appetite and resulting portfolio shifts from stock markets to bond markets.
• In early March, the Egyptian Government is organising an international conference in Sharm el-Sheikh in support of the Palestinian economy for the reconstruction of Gaza.
• Compliance with minimum standards during the coming local elections in early March would be a second step, followed by a convincing commitment to fulfil all the conditions outlined in Parliament's draft resolution.
• In late February and early March this year the Danish authorities made hundreds of arrests following the protest demonstrations in Copenhagen against the closure of the Ungdomshuset, and 30 people are still in detention awaiting trial.