Grounds for appeal against late payment of tax

I have a new client who has been working abroad and paying foreign tax and did not realise he had to complete tax returns and possibly pay uk tax.  He received a repayment of tax deducted through paye for the first half of 2009.  He thought it odd so came to see me.  We then contacted the HMRC and completed the 2009, 10 and 11 tax returns within a month and he paid all outstanding tax for 2009 at the same time.  He was charged interest and paid that.  However he has now received 2 surcharges for the 2009 tax saying it was still outstanding after 28 days and 6 months after the due date.  Can I appeal? What grounds?  Should the due date for the tax be the date the tax return was sent in or the original date of 31st Jan 10?  Can anyone advise me please.

Thanks  Jean