I'm sure someone could say that Casino Royale takes place before the events of Dr. No if they wanted to. There's only one snafu, Bond meets Leiter for the first time in Casion Royale, seem a bit odd for him to then meet Leiter again during his next mission.
Fanwankery= Felix Leiter is a codename.
There's only been a limited continuity of actors anyway with Hedison being the only one to have reprised his role (yet).
Another issue is that (apparently) we see Bond get his 00 status, however in Dr. No
he's already a secret agent.
Other factors such as the Russian army in Afghanistan (instead of the US Army), the references to Cold War and Soviet Union and the use of the gold standard (which was abolished in 1971) etc etc already date the original series so that it cannot any longer be in the present day.