No. Regional meet ups are community-led and anyone can organise one. You do not need to be an official SCA UK volunteer or have any formal role. If you want to bring a few local members together, you are welcome to go ahead.
That said, we are happy to support you. Let us know you are planning something by posting in our community, and we can help you promote it to members in your area. We can also share it via our wider communication channels if helpful.