Thanks for the reply, Drjad - good to see that your understanding was the same as mine.
Specifically with regard to the Vale of York, though, there is no equivalent recommendation to avoid the area. Column 2 for the Vale of York reads: "Pilots transitting the area are advised to maintain constant vigilance and a LARS is available from [details of Leeming and Linton]." Quite different to The Wash, as well as the three other AIAAs that I listed.
FFF
----------------