Thanks for your reply. Saw the mail notification earlier and played with your 'improved' version. Now it's 146 char long from before 160 and substituted the old whereever it showed in the workbooks.

Bug or feature, I've been unable to derive where 255611462399 seconds might have been coming from.

Pity your MS MVP crystal ball is as hazy as mine with regards to what's being fixed. Maybe I'll have a look at the OF2015 test release. Curious is, if using d:hh:mm:ss as text mask, the feedback value is 31:23:59:59 or 32 days minus 1 second. Did not find [d]:hh:mm:59 as working. Pity as that would have allowed to reuse the days determined... 2958100 it seems.

Anyway, Thx again.