I live on Lanzarote and June is a little bit early for trade winds but you could be lucky and get epic conditions. As when the tradewinds start to kick in you either have good conditions or nothing. 3 days on 3 days off but once they come in windy every day.
On a freestyle board my largest sail is a 4.7 and I'm 62 Kg. With a 5.2 as my biggest but I don't like using it much. Most people here there largest sails are 5.3's.
To be safe you should bring your 6.0m.