Remember the volcano and BA strikes.
I think it will reflect in the Annual results, however to use your name, it doesn't take rocket science to work out how much the profit would have been if you average the other months and assume the same yield for the couple of lean months due to external influences.
Remember, NATS have stated before (to keep pay awards down) that one-off profits (EGLL tower sale to name but one) should not be used as an indication of underlying profits...
The exact same can be used the other way - one off events that reduce profits should not be used to try to claim the company is not doing so well. I'm sure the union are well on top of this.
As an aside, we often hear of our customers and how they are finding it hard. I believe (from another source) that BAA and Virgin have recently given good pay awards to their workforce...