It normally takes 14 days to activate, so 3 weeks should be ample.
Check your account names etc. are EXACTLY the same on O2 and VM, as this can cause the VOLT upgrade to fail.
Also check the conf settings on the Hub. It will show what speed has been provisioned.
It's Configuration tab - Primary Downstream Service Flow - Max Traffic Rate.
You could also try a factory reset to force down the latest config file to your Hub.
Remove any ethernet cables from the Hub and hold the pinhole reset switch for 60 seconds. Do NOT reboot the Hub, just let it do it's thing. Note you will need the passwords from the bottom of the Hub afterwards, so make sure they are legible.
If you wait here a day or two a VM Mod will pick this up.
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