Transition from portfolio building to charging

Hello! I have pursued food photography as a hobby over the past 9 months. I’ve invested in courses and have shot at home every single weekend to build my skills. I recently began pitching to restaurants to shoot for free to help build my restaurant portfolio. At this point I’ve shot at two and both shoots went well. I reached out to numerous restaurants back in April and two are getting back to me now with the expectation of a free shoot, per my original pitch. My question is, at this point I feel like my work is definitely worth charging for. Do I honor what I requested 3 months ago (free photo shoot) or do I let them know that at this point I’ve transitioned to charging for my work? My gut says the latter, especially given that three months have passed since my original request but I’m wondering if there’s another perspective I’m missing here. Thank you!