I’ve been in July, and although not a biking holiday, I did get a day riding on a rental bike. Rode up as it was last minute and all the uplift was fully booked. It was high 30s, so hot, but not too bad really, climbs on the road were the worst! Didn’t see another mtb rider all day! Trails were great, did some natural stuff off of a map the shop let me borrow, mainly towards the south of Finale I think.
If it’s the only time you’ve got, I’d do it. I’d go again in July, only downside perhaps was that the kids found the sand on the beach too hot to walk on! So we spent all day in the water. Oh, and paying to sit on a beach took some getting used to!