A follow on to the British Deaf Association publishing a BSL teacher directory, suggesting no shortage of teachers to develop a BSL GCSE. Factually, teaching BSL in informal settings a few hours a week doesn't actually qualify them to teach in schools via the curriculum without additional qualifications, the only 'exemption' is if the pupils are deaf etc, even then conformity to the curriculum is essential, they cannot ignore English or its grammar e.g. and NOT if the students are hearing.
The official declaration:
To teach in a mainstream school, BSL teachers generally need to meet the same qualifications and requirements as other subject teachers. This may include having a teaching degree or certification, as well as any additional qualifications specific to teaching BSL or working with students who are deaf or hard of hearing.
Additionally, BSL teachers may need to adapt their teaching methods and materials to effectively teach hearing students. They may focus on teaching BSL as a foreign language, enabling hearing students to develop communication skills and cultural understanding of the deaf community. The curriculum may include sign language vocabulary and grammar, deaf culture, and communication strategies.
