time remapping script recently broken - rounding issue, has something changed?

hi all

I have a time remapping script that I have been using for literally years that has suddenly stopped working properly.  The issue I'm having is the values I set with the script are correct, they're just no longer being applied properly to the time remap keys.

If I set a value and then check to see what the property value is, I get some very odd, close but not exact number, and in the UI the non-exact number is getting rounded, often to an incorrect frame.... so annoying!!! I've never had this problem before. It is like something has recently changed internally with the time calculations.

Any suggestions on how I might resolve this or possible trouble shooting options would be greatly appreciated...

ps. here is a snippet from the debug console showing the value i'm setting and then what Ae has actually set (or at least what it reports being the current time remap value) 

I generally use 25fps as it so much easier to work with frame durations of 0.04 secs but I realise Ae is doing internal calculations using ticks or some such.