Well I don't want to reply as if I'm giving absolute answers, but my guess would be that what it means is that, say the phone went into the recycling bin and after it got to the recycling centre the phone was crushed, then the phone wouldn't be able to send out an "I'm turning off now" signal so it would still be in a sort of loose connection on the mast as the mast waits to see if it gets pinged again? But it doesn't get pinged again.
I don't know whether the battery going flat would have the same effect. From what's been said on here, our masts should have the same turning on/turning off communications with the mast, but I don't know if they're recorded or notated in the mast data?
Or, as Nicola's said, say the phone turned off in one of the 'blackspots' where the phone can't communicate with the mast, then would have the same effect, but from what Nicola's said there's a delay on the mast picking up a phone, so I am guessing that the phone could send a signal as it reaches the outskirts of the mast area, then enter a blackspot and be turned off/run out of battery, then the delayed signal is noted by the mast, and then the phone appears to stay on the mast for 3 hours but in reality it could move anywhere, and being in an 'off' state, it won't get picked up by any other mast.
I hope that makes sense and that I got it all right.
I don't know whether the battery going flat would have the same effect. From what's been said on here, our masts should have the same turning on/turning off communications with the mast, but I don't know if they're recorded or notated in the mast data?
Or, as Nicola's said, say the phone turned off in one of the 'blackspots' where the phone can't communicate with the mast, then would have the same effect, but from what Nicola's said there's a delay on the mast picking up a phone, so I am guessing that the phone could send a signal as it reaches the outskirts of the mast area, then enter a blackspot and be turned off/run out of battery, then the delayed signal is noted by the mast, and then the phone appears to stay on the mast for 3 hours but in reality it could move anywhere, and being in an 'off' state, it won't get picked up by any other mast.
I hope that makes sense and that I got it all right.
I can't quote your summary but I can't see how the bit about a phone staying a mast for 3 hours is true unless she means that it will stay there if it doesn't move within 3 hours which I suppose would make sense.
My understanding would then be that the phone pinged the mast at 5am and then nothing was heard for another 3 hours so the possibilities are that it stayed still for 3 hours or stopped transmitting during those 3 hours and now could be anywhere - is that right?
It still doesn't fit with what I've read in other cases where it was possible to identify whether the phone run out of battery or was switched off but as these cases were in Amercia it may be that things work differently there