[Duma]

Any reason I def shouldn't do this? Obvs the sea will be cooler than Sept but from a look online it seems not to cold.

[Danny]

Had a fun early season trip to Sardinia a few years ago where we did some light DWSing. I recall the water was surprisingly cold, but other than that it was fine. I've heard seepage is a major issue in the midsummer at Diablo, but perhaps it's ok early season? That might be the only potential problem.   

[Paul B]

For Mallorca DWS you want the sun low in the sky to get rid of the grease that develops in the back of the caves.

[Ged]

Went in June once and we had real issues with grease. A lot of crags were unclimabbale. As above, go in Sept or October when sun is lower in the sky.