When will the price of a stamp go up again?
When asked about putting up the price of First Class stamps today, Royal Mail's chief executive, Moya Greene, said: "It would be improper of me to give assurances on price."
The point is that Royal Mail now has the freedom to set whatever First Class price it wants. It went up from 46p to 60p in April.
Ofcom still controls 2nd Class, 50p at the moment, and has laid down that this can't rise above 55p (plus inflation).
Royal Mail's return to UK profit today lifts the pressure to raise prices a bit.
On the other hand a business with £3.6bn in revenue over just six months will be looking to make even more than the £99m operating profit reported for the half year to September.
The fact that a public sale of Royal Mail is pencilled in for next year will only spur them to boost income, to try to make the business look more attractive.
So brace yourselves for more stamp prices rises in the spring.