Hi Paul...it's called "the mouth of the valleys" - used to be caller 
Dave Parson's nickname in the Rhondda -

32 bar polka/reel march

5cpls in a pentangle / circle (wrote it for 5 then realises it works as 
a partner change for any number...but it's for 5, dammit!

a1 men reel. the men dance across in front of their partners, round 
behind them, in front of the "other" w, round behind her & so back to 
place (other = w next to him that's not partner)

a2 w do same

b 1& 2 Face partner. check behind. that's who you end up with. RRHT 
partner until you face other. LHT other until you face partner RHT 
partne until you face other. Give left hand to left hand ; man turns to 
face same way as wo to make a promenade hold. prom to end of music.

I like it because it flows. even the turn into the prom, if you get it right