I had a couple of rides out at the weekend; not completely flat, but with very little climbing.
Saturday was a steady solo in gloomy weather, but Sunday was a very warm day. I left it until 4:30 and doused myself in factor 50, which seems a strange thing to have to do in the UK in May.
I am finding it difficult to keep to 120 HR, not because my heart is out of control, but because I feel healthy enough to go faster. However 130 still makes me short of breath in the way that 165 would have done 18 months ago. I am still only four weeks on from the operation, so I am continuing to restrict myself on HR while trying to go further and more often.