Not so much! I assume you mean that you mean LM of the Senco and not the Senco Line Managing TA’s etc?
So if Im correct…. Without taking the full course for the NASENCo for you, if it is knoweldge etc and understanding the role of a SENCo and being able to challenge robustly, resources on the key might help. They have a shorter course with needs to know parts of key legislation and key documents that a SENCo should do. Otherwise it comes into general LM. We can be difficult to LM as often the width and breadth of the role is so vast (I am a SENCo but also been SLT so see both sides).
I hope I havent interpreted the question wrong, let me know if I have