Is it just about pitch?
No, and this is the most common misunderstanding. Raising pitch alone tends to produce a voice that is strained and does not read as more feminine. Resonance — where the voice sounds like it is placed — and intonation patterns do at least as much work, and they are what a structured course spends time on.
Pitch is still worth measuring, because it is the part that is easy to quantify and to track. It just is not the target on its own.
How long does it take?
Longer than most people expect, and it varies. A course designed around ten minutes of daily practice assumes months rather than weeks, and the gains are cumulative. Short, frequent practice is generally more effective than longer, occasional sessions.
Can I do it without a speech and language therapist?
Many people do, particularly where waiting lists are long or access to specialist speech and language therapy is limited. A structured course led by an expert in voice feminisation provides clear and practical guidance.