PIP is not affected.
You can have a full time job & still get PIP.
It is awarded based on your needs relating to your disability/health to help you in your everyday life.
If you only get PIP & nothing else, there is nothing to stop you trying to earn money.
It's the rest of someones benefits you need to check up on.
Housing benefit, ESA or whichever legacy benefits are the ones that can be changed.
If on legacy benefits & nothing changes, a claimant will have transitional protection when moved onto UC (everyone is supposed to be moved onto it within the next couple of years).
That would mean that as long as nothing changed, they would receive the same amount of money until the rate of UC for someone in their position rose to the same level which could be several years.
If a change the DWP count as big enough happens, this can trigger a move to UC.
UC pays different rates.
Some people are better off on UC, some people are not & nobody on Mumsnet can tell you which they would be.
You wouldn't lose benefits forever, but could be on a different rate which could be lower.
I know people who have lost almost £100 a week after moving to UC.
If they hadn't moved, they would have still been getting that extra money.
Once you start a move to UC, you cannot undo it & go back to legacy benefits.