Our cat went missing when we were away in the summer. She had been run over and taken to the vet's by a kind neighbour. Unfortunately, she died. It might be worth contacting local vets as they are only obliged to keep dead bodies for 7 days.
Also check bushes near the road as if hit, the cat may have crawled to the side. Also garages. Might have got shut in.
May be fine, of course, and hope that is the case. None of my cats have ever disappeared when we were away other than the one that got killed.
I think that you should stress that you are doing everything possible and there is no need for them to worry unduly.
Tell them that you have heard of loads of stories of cats going missing whilst their owners are away, but as they are new to the area you thought it was worth asking if the puss could have gone to a previous address.
My cat used to hate being fed by the neighbours and regularly buggered off for a week when I went away so it is quite possible that this one is the same.
it's perfectly possible that the cat has taken excepion to dh (who wouldn't?!), or more likely, our 3 year old dd1 who went with him to see 'her friend' the cat the first few times. stupid idea. cats and toddlers don't mix.
we will indeed be as optimistic and low key as we can be when we text them. bit dire making decision for someone else. hate to spoil their travels.
Putting the shoe on the other foot..if I were on holiday and my cat went missing. I would rather finish my holiday and return home to be told that the cat was missing and the minders had done their best to track it down. Than to spend the rest of my holiday worrying about the cat (and the minders) and not be in a position to do anything about it.
You could contact the local cat rescue places too, incase it has been handed in. Also the local council. Apparently they can be called to dispose of cat bodies, so of you phone them with a description they should be able to say.
The cat might just be keeping a low profile, and reappear when the owners come back.