The dates are all very similar and the mast is 1552' AGL, so shouldn't be susceptible to 100' rounding errors. Thanks for your efforts. I know it's a trivial point, but it's starting to really bug the OCD part of my brain! I think I'm going to have to contact No1 AIDU who supply our documentation to see if they know why (or if it's a misprint that no one has ever questioned).
If I have any luck, I'll let you know
