Postage Beyond A Pound?

Royal Mail says is probably going to raise the cost of sending a letter.
That would be a second increase following the increase in April that took the price of a first-class stamp to 95p (a 10p increase) and the cost of a second-class stamp to 68p (a 2p increase).

I think the time has already arrived when some people look at the cost of a greeting card, and mentally add the unacceptable cost of the stamp and decide it is just too expensive to send a card at all.
Our cards retail at £2.40, with postage on one card at 76p. With four cards, it is postage free. Our prices are lower than some, but the extra 95p for postage pushes it to £4.11 – and that is not insignificant for some.

What happens when Royal Mail pushes the cost beyond a pound?