This paper provides an update on the current status and future challenges in the field of wearable photoplethysmography, an optical sensing technology which is widely used in wearables such as smartwatches. It builds on 'The 2023 Wearable Photoplethysmography Roadmap', an article in which 51 leading researchers provided their insights into the key research required to realise the full potential of wearable photoplethysmography. Firstly, this paper presents the findings of the Roadmap. Then, further developments in the field not covered in the Roadmap are discussed, including conducting large-scale studies with wearables and advances in signal processing and machine learning. Finally, reflections are provided on the process of co-ordinating a Roadmap article.