You can upgrade or downgrade to a different tier of Boost membership at any time.

If you are upgrading your Boost membership you will be charged a pro-rated difference in the membership fee and will be able to enjoy the benefits straight away.

An example of a membership upgrade:

I upgrade from Light Boost to Turbo Boost 22 days into my membership, which is around 75% into the month.

So I need to pay for 25% of my Turbo Boost subscription which is the rest of the month: 25% x £8 = £2

And I also will get back 25% of my current Light Boost membership that I have already paid for: 25% x £2 = £0.5
Therefore my upgrade payment is £2 - £0.5 = £1.5

If you are downgrading or cancelling your membership you will still be able to use the benefits of your membership for 30 days from your latest purchase.

Warning! Cancelling your Boost membership will void your outstanding kWh balance from the Refills.