Spongy floor

I recently purchased a 2020 Malvern. Concerned that floor between fridge and cooker was soft and creaky. Returned to dealer to be told this was normal. Water and gas pipes cross the van within the floor here. My concern is I occasionally hear pump kick in. Dealer says this is normal as pressure balances out.
This is my fifth van. Never experienced a floor like this and previously pump activating meant water leak.
Thoughts please.

On my Nuevo there is a bit of sponginess in the floor in front of the fridge.  It's been like it since new and is most noticeable when the fitted carpet is removed.

If you have the Whale, in my experience it's normal for it to keep coming on for a few seconds.  This was the main reason we had ours replaced with a Shurflo which does it much less frequently and for a much shorter time.  I believe it happens when the water cools/contracts.  When the water heats up/expands, the Truma frost/pressure relief drain valve can be heard opening which sounds like a short creak.

Other reasons for the Whale pump coming back on are leaks including a leaky Whale Non Return Valve (NRV) (integrated with the Whale pressure switch) allowing pressurised water to flow back into the freshwater tank.  The NRV can be dismantled and cleaned.

Hi I have been having similar problem with our Winchcombe , went back to dealer and had it repaired , it was a floor delamination ,repair did not last so had to take it back a second time for warranty job , the floor is doing the same further along so going to repair it myself this time , it appears to be a bit of an issue with these vehicles , ours is a 2017 model , will be using something like this 
https://ctaltd.co.uk/product/caravan-floor-delamination-repair-kit/
As for pump it is sort of normal the valve leaks a bit internally causing a drop in pressure then it kicks in and builds back up again , not an issue really we just switch it off during the night , but everyone to there own 

More likely due to age the foor in our Rienza is spongy between the wardrobe and the fridge were the pipes cross under the floor. It’s not got any worse over the years and I don’t want to risk damaging a pipe trying to repair it.
Our water pump runs for a short burst after the water heater has been on. I was told it was the heater cooling down so just another foible we have got used to.