We present a case-study of using Ethnographic Experiential Futures (EXF) to surface underlying divergences, tensions and dilemmas implicit in views of the futures of ”social agents” among professional researchers familiar with the state of the art. Based on expert interviews, we designed three ”letters from the future,” research probes that were mailed to 15 participants working in the field, to encounter and respond to. We lay out the elements and design choices that shaped these probes, present our remote and asynchronous study design, and discuss lessons learned about the use of EXF. We find that this form of hybrid design/futures intervention has the potential to provide professional communities with opportunities to grapple with potential ethical dilemmas early on. However, the knowledge and tools for doing so are still in the making. Our contribution is a step towards advancing the potential benefits of experiential futures for technology designers and researchers.