Savvy
There is an app now called Livi NHS where you can get a video consultation with a GP the same day, my surgery told me about it when I couldn't get an appointment. As long as your records are available for them to see, they will call you free of charge for a video consultation. The outcome and notes from that is fed straight back to your GP surgery so they can follow up if necessary.
From their web site
If you’re not yet eligible you can choose to use our pay-as-you-go service instead.
Presumably you have to sign up to find out if you are eligible.
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