In uk.d-i-y, Frank Erskine wrote:
As a bit of a genealogist I fairly regularly send a sae of C4 size
folded in another C4 envelope with application forms and cheques for
civil registration certificates, and have been hit by this new
charging scheme. Obviously it's nice to get a certificate unfolded -
that's why the C4 envelope. Royal Mail told us that most postage
should cost less, but when I sent mail recently it was received with a
sticker attached "..... On this occasion you have not been surcharged
but in future you may be. Please contact the sender.", so most of my
posting will cost more than hitherto.

Most of my posting is CDs in jiffy bags. The price has gone down for me.

Also (not connected with the above) I've seen mention in this thread of
dodgy kitchen scales. They needn't be. Modern digital kitchen scales are
perfectly adequate for 99.9% of postage purposes.

--
Mike Barnes