No, Dunhill tins cannot be accurately dated. I would say that some of them can't even be accurately tied to a specific manufacturing era without seeing both the lid and the bottom label. I've seen tins with painted lids bearing the "made in the UK" legend, which typically indicates a Murray's-era tin. Yet when you turn them over, they clearly bear the new import label associated with Orlik and, in fact, say that they're manufactured in the EU -- not the UK. So these are transitional tins, where apparently Orlik was using old, Murray's lids with Orlik-blended tobaccos. It wouldn't shock me if a similar situation could have existed when production originally shifted from Dunhill to Murray as well. After all, why waste all of those lids. . . ?
Bob