UK Hair Dye Formulation Needed

My goal is to launch a professional-grade hair dye that can be produced at scale by a contract manufacturer in the United Kingdom. I already have brand positioning and target shade range defined; what I do not have is a fully validated, production-ready formula.

Here is the support I need from an experienced cosmetic chemist/formulator:

• Create a complete hair-dye formula that meets UK/EU cosmetic regulations, including INCI list, percentages, and processing instructions.
• Supply bench-scale prototypes with stability and performance data (wash-fastness, grey coverage, skin-patch irritation).
• Advise on ingredient sourcing that keeps the supply chain within the UK or EU where possible. I am particularly interested in options such as ammonia-free systems, long-lasting colour technologies, and the use of naturally derived actives; I’m open to your professional guidance on the best route to meet those claims.
• Prepare all compliance documentation required for manufacturing and sale in the UK (CPSR, SDS, CPNP notification pack).
• Provide a tech transfer pack for the chosen contract manufacturer, including quality control specs and batch-sheet instructions.

Acceptance criteria: the final formula must pass a 12-week stability test at 4 °C, 25 °C and 40 °C, achieve ≥90 % grey coverage in salon-standard tests, and be fully documentation-ready for regulatory submission.

Please outline your experience with oxidative or direct-dye systems, any UK manufacturing partners you’ve worked with, and an estimated timeline from brief to pilot batch.