We have one of those folders also and like you, paid to get it originally but did not renew it (in fact I actually came out and advised against renewing the DXGC through GDT).
The decision to renew it or not should depend on what you are using your DXGC for. Originally we were told that GDT would be providing further information on how to operate your DXGC but, as with all things DX, that information never materialized and so we didn't actually use our DXGC for anything.
It can be advantageous to hold an offshore company for various reasons and if you have plans to do this then I would suggest keeping it up to date ... BUT find out how to do this directly with the Vanuatu authorities and do NOT use GDT as the middle man (if fact I don't even think there is a way to renew your DXGC through GDT at the moment ... but that's alright because GDT don't believe they need an online website at the moment

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