Inconsistency in test results from different sites

Hi all,

When testing my site from Amsterdam NL - IISpeed, I get an F for cache static content. From London UK - EC2 I get a B or A.

Amsterdam
http://www.webpagetest.org/result/171124_H2_e18ca4fde9274c1bd1ccadec71266fd7/

London
http://www.webpagetest.org/result/171124_HP_30e633ba624afbe70ea672f68b13f1cf/

Is this normal?

Thanks for looking