RAF dark green

H116 is FS 34079 Dark Green. It is an aircraft colour. We used it in the RNZAF for our A4K and MB 338 camouflage schemes.

Humbrol is my main choice for paint and like you H30 was used for RAF green - i've since changed to H163 on good advice, although a Satin finish this green looks much better, i use Matt Revell varnish's tho after some bad experience with the Humbrol stuff.
H116 is listed as a US Dark green, presumably used on armour ? it 'cross ref's' to a Luftwaffe shade also !

I don't use Humbrol so can't help you on that. Until they stopped production, I used Aereomaster RAF Dark Green. Now I use Model Master RAF Dark Green which appears to be slightly darker than the old Aeromaster but still looks good.

Rick