You are getting a bit mixed up between tax returns and tax payments. Preliminary tax is a payment of income tax, there is no preliminary tax return. Ignoring extensions for ROS filings, Preliminary tax is due by 31 October in the tax year concerned. Therefore for 2009, the preliminary tax payment is due on or before 31 October 2009. Preliminary tax can be based on 100% of the prior year liability (i.e. 100% of the 2008 liability for 2009) or 90% of the actual liabity for the year. Therefore if 2008 was the first year that your husband was self employed he would have had to pay his 2008 liability on or before 31 October 2009 and a preliminary tax payment for 2009 on the same date. There is only one tax return due each year and that is due by 31 October following the year. Therefore the 2008 tax return was also due on 31 October 2009.
Your accountant should definitely of highlighted the need to make a preliminary tax payment. Especially as there was some complications to calculating the preliminary tax last year to take account of the income levy,.