Well after dreading it all day, I went out and completed the 25 min run. It seeemed to go by really quickly, and I kept it quite slow. It wasn't easy, but I definitelly didnt find it as hard as W6R1. The evening was cool and dry which also helped. Managed to cover 2.5 laps of the park so about 2.5 miles in total. 30 mins definitely feels like it is now within reach.