Unfortunately you've edited your post heavily. I was going to answer your questions, but now I only see your original post in the other window.
Exploration Ships don't put people in those probes, at least I hope so, otherwise they'd need a constant flow of clones, which are expendable. The probes, and, of course, the clones, too
I still struggle with the use of the words
exploration and
survey in DW2. For me being not a native speaker they are not used in the way I'd use them. But than again, I'm not a native speaker...
You start with peopled "Survey Scanners". Each "Survey" takes up "Survey Time". The first "Survey" is good for an "Exploration level", see planet, of "Survey Amount" while any follow-up "Survey" increases this number by "1" up to an "Exploration level" of "Survey Maximum Level".
"Exploration Scanners" work similar. Each "Exploration" takes up "Exploration Time". "Exploration" is good for an "Exploration level" of "Exploration Power", and that's it. You can't add further "Exploration". "Exploration" also works on distance, see "Exploration Range", which speeds up exploring asteroid belts significantly.
"Exploration" is fast but limited. "Survey" takes longer but reveals more.
The wording just feels wrong, it's more confusing than enlightening. "Exploration" and "Survey" are used to describe the components in a way that... anyway, I'd just repeat myself again
I hope I was helpful and didn't cause more harm to your understanding

- Manual, page 35
- image_2022-08-14_145051005.png (515.39 KiB) Viewed 991 times
As for the "Exploration level", this value can go up to 255, or 0xFF, it's just a byte and it's limit are its bits

Any resource, facility, and bonus has its own "Discovery Level" which is just another term for "Exploration level".
Once a planet's "Exploration level" is equal or higher than the highest "Discovery Level" it houses, the "Exploration level" turns green. Population, stations, and bases will raise the "Exploration level" up to 255 over time. They all have nasty little buggers that can't stop looking for new things even when the game knows that there are no more hidden things to find - until the demigod with their mouse decides otherwise

Or a game event creates a new opportunity in which case a higher "Exploration level" may become useful.
Use the Game Editor to dig into it.