Medium-enriched is generally defined as anything in the 10-90% enrichment range. The IAEA is extremely clear that Iran possessed medium-enriched uranium as far back as 2010: https://www.iaea.org/sites/default/files/documents/gov2011-6...

We all know how cascade enrichment works, having 20% or 60% enrichment is still not equivalent to having the bomb. It is directly commensurate to the "Iran is N weeks away from the bomb!" because people are just extrapolating enrichment time without any other metrics included.