I think we are talking about - I2181 4606-4447 calBCE - as the earliest R-M269 so far. He's only a couple hundred years older than the R1b-M269>L23 MRCA.
I2181 is at Smyadovo, Bulgaria, on the west side of the Black Sea and only about 300 km/190 mi from the Sea of Marmara.
This doesn't really help the Corded Ware route case unless his EHG autosomal is a sign his offspring didn't get to Iberia early (edit: before 2500 BC and the supposed reflux and/or Steppes auDNA Beaker folks entrance to Iberia - with a chance to bear the P312 MRCA).