Airey Middleton Neave was held for a relatively short period at Stalag XX-A from Feburary 1941 to the April '41 when, with Norman Forbes, he escaped. Re-captured by the German's as they headed for the Russian held lines near Itow in Poland, Neave and Forbes were returned to Stalag XX-A and were then moved to Oflag - 1V - C otherwise known as Colditz in the May of '41. If you are interested you can find out more about Neave's escapes in his book "They have their exits" which you should still be able to obtain from your local library. The book may not mention William but it may give you an idea of what it was like for him at Stalag XX-A.
old rowley