For what you say to hold true we have to assume that the overall picture
has remained constant, but we know that it hasn't and global temperatures
are higher now than at anytime since 1890. Therefore the basic background
'constant' has changed and what went before cannot be applied now.

Also is not the opposite of this true, statistically -
"Before then we have to go back to February 1963 and of course January 1963,
a gap of 16 years. So on that basis, yes we are due." If we are in a mild
trend isn't it less likely to happen than if we were in a cold trend,
irrespective of what happened before.

Dave