From Fallen London Wiki

It's still just dropping broadly linearly. :-) I'd post a new graph, but it's not excitingly different. Current target end date is 21 Jul 1899 (2024), allowing for the pyramidal drop-off below 50. That's slightly later than before (a shift of about two days) which, if it continues, may shift the date out even further (perhaps three days later to 24 July).