PTSB Interest calculated wrongly?

So my interest arrived in my PTSB savings account today, but as far as I can tell it's wrong. The rate was 4% until Sept 15, and then went to 3.5%, but it looks to me like the full interest amt is based on a rate of 3.5% being in effect for the duration.

If I had e1000 in the account, I calculate that I should get 258 days (1/1 to 15/9) at the daily rate of 0.04/365 and then the rest @ 0.035/365. Am I wrong in this calculation? It looks to me that I'm simply get the whole lot at the daily rate of 0.035/365.

Anybody else with a PTSB savings account get less than they expected?

Put up the actual figures for us to have a look at.(or give us the per 1000 figure if you don't want us to know how much you have)
Don't forget dirt.

Oops, never mind. Turns out I was calculating deposits entered in 2011 incorrectly (ie, I was calculating them with an extra year's worth of interest, and not taking into account interest already paid last year. As an example, I opened the account in 2010 with 1000 euro. That will earn about e39 interest (before dirt) each year, but I was calculating that it would earn e78 in my sums.

I owe the bank an apology :}