They are claiming about 1/8" of rise per year. Would you have noticed a change that small and that slow? That equates to a mean low & high tide change of 5.5" over that 45 year period.
If available, it might be fun to pull local tide records to see if there really has been a slow rise over the years.
Proof positive that the sea level is not rising, as the sea level is still at the waterline.
If it was rising at the rates claimed, the lower gun deck would be awash after more than 225 years.
Hey, it makes just as much sense as most of their claims!