09 General Relativity.
People or objects at the top of mount Everest may change slightly more rapidly than people experiencing the stronger gravity nearer the Earth's centre of mass. But this change is 'just' happening.
If this change is constantly happening 'over time', then it must be the case that the top of Mount Everest is 'constantly' slipping 'into the past' more and more, or base camp one must be constantly moving into the future.
While the top and the base may well be changing at different rates, surely, unless you can prove that 'time','the past' and 'the future' really 'exist', it only makes sense to say that all such relativistic effects happen not 'over a thing called time', but just happen 'now' (so to speak).
General Relativity suggest 'time' distortions over gravitational fields. What this means is that a person in a strong gravitational field will age, or rather change, slower than someone in a weak gravitational field.
This is useful in proving whether time or timelessness exist, because we can situate two observers stationary relative to each other, and then apparently watch 'time dilation' effects.But if you imagine a chain of climbers holding hands all the way from the base of mount Everest to the peak, then relativity tells us all these people, all constantly physically touching and communicating with each other, would be ageing at different rates along the chain.
No matter how small the effect on earth, the effect is still real, in that it has been tested by atomic clocks, and shown that clocks at different altitudes run at different rates. (the higher the altitude the weaker the earth gravity, the less 'time' is restricted in its flowing)
However, we can also see that all our climbers would never see a distortion through time. the slower ageing ones nearest to the Earth's centre of mass may 'change' more slowly, but they never sink into the 'past', because time does not exist, or pass or flow, and there is no past to sink into.
So the effect that general relativity shows us (and calls 'time dilation') is not that time exists, and passes, (and thus that the future and past exist), and not that the rate of the passage of time can be changed. But only that things change, and the rate at which they can change 'now' may be varied under different conditions.
For a thought experiment analysis of this effect see...