I have currently X amount of waves staked. If I

unstake them for 1 minute, and then stake them again, will I loose 24 hours of rewards?

How often they usually take snapshot? Once per day? And is there any period in the waves protocol during which freshly staked tokens don't receive rewards?

We do not regulate the payment process, so please carefully read the terms of payment and do your own investigation of the pool that you use or contact the pool owners to clarify it.

OK, but generally speaking, if I unstake and stake again in 1 minute, I don't lose any rewards unless they take the snapshot during that 1 minute?

At least Around 16hour

I lose 16 hours of rewards?

You shouldn't.

If you've pasted 100 waves now, it won't start rendering for 16 hours. If you had 100 waves and took 50 waves now, usually your 100 waves reward has only been validated until the current block. If you again put 50 waves, they only started to render in 16 hours. This is a technical limitation, it also depends on the node's payment model. But at least you are already limited to 16 hours on any node you choose.