When to start reaching out to Angels? (I will not promote)

Hello all, I would appreciate some guidance navigating my plans. Start of next year, I plan to pursue a year long masters to give me a specific skillset, industry insight and networking (including potential manufacturers, and industry leaders). When would be the ideal time to start to connect with Angels for pre-seed funding? For more context; - Its in the apparel industry. - The masters will be in a foreign country, I have no plans of living there afterwards. I will likely HQ in England. - I’ve been writing the business plan for the last few years and refining and factoring industry developments. Any insight or advice is appreciated. Please no sarcasm. I will not promote. Thank you!