Posting Dilemma

I've always had a thing about post boxes, and tend to photograph them all the time on my travels. Apart from being very graphic objects- all that red and black and seriously heavy cast iron- they can be a history lesson in who was king or queen at the time of the erection, as it were. The ciphers cast into the iron can be anything from Victoria's to our own Queen, with a handful cast for Edward VIII before he abdicated. Most boxes in urban areas will be pillar boxes, with wall boxes and boxes strapped to telegraph poles proliferating in the countryside. I am intrigued as to what happened here at Woolpit in West Suffolk. Presumably the wall box capacity became too small, but you wouldn't have thought the demand for posting to have grown that much between George V's reign (the wall box) and George VI's (the pillar box). I love the fact that they are both still in use, the wall box announcing that it's 'for large envelopes please'.