Long-term Machin collectors - especially members of the Modern British Philatelic Circle - will be aware that a number of forgeries have been prepared over the years, from the early and poor-quality 24p brown, through to modern 1st class (or even £1) stamps.
It must be improving print technology and lower prices for equipment and materials has led to a proliferation of quite good-quality forgeries of the 1st class red with security features! The one thing that eludes all the forgers is to properly reproduce the phosphorescent ink.
Quite often these forgeries pass through the mail system without difficulty, but I have now been shown an example which was picked up by the automatic sorting equipment, and not cancelled. Upon examination it was first cancelled with the wavy line handstamp now (not often enough) used instead of the good old ball-point pen, and then the stamp was identified as a wrong 'un. I've not seen this COUNTERFEIT STAMP handstamp before. Being unpaid, the new £2 standard charge for an unpaid letter was raised, with the yellow sticker applied.
I don't know how old this is. The stamp coding is MTIL M13L which means it could be nearly 4 years old - or it could have been used late last year.
UPDATE: Rob has identified the competition (correctly) from the limited amount of address shown; it was published on August 28 2016, so the entry would have been posted within a few days of that date.
25-day Journey from Berlin to Esch-Alzig in 1943 - Berlin W.15, 13 Aug 1943 Esch-Alzig, 7 Sep 1943 25-day journey! 4.5 kg = 60 Rpf. [Zone 4] Delivery fee = 15 Rpf. In August 1943, the war was not going we...