We will need a shareholder special resolution in order to amend the provision in the articles of association re accounting year. Such shareholder meeting requires at least 14 days' notice. We need a few days before to prepare the notice, arrange for the signing by directors and the advertisement. Strictly speaking a board meeting is required before holding a shareholder meeting (but we can backdate the notice and minutes if you are OK with it).
In addition, you also have to apply for the change of accounting year with the competent Revenue Office (they may ask for board resolution or shareholder resolution). After the Revenue Office has granted the relevant approval, you have to submit the application for said change at the Department of Business Development.
For the Revenue Office, a number of documents such as tax returns, etc. are required with the explanation letter and power of attorney. You will also have to prepare audited financial statements for Jan to Mar of the year of the change.