Not a big deal, I am able to ship the order today but I want to understand what went wrong (standard FBM).
Yesterday afternoon, I changed the handling time on my general shipping settings from same day to 2 days so that the next ship day should have been Friday by my calculations.
An order was placed Friday night at 23:38 which shows ship by Mon, 23 Dec 2024 GMT to Tue, 24 Dec
My other settings are:
Automated handling time - Not active
General Fulfillment Settings (non-Prime) - Operating Days - Monday, Tuesday, Wednesday, Thursday, Friday
ASIN specific - no handling time set
There is no cut-off time anywhere that I can see which denotes the "end of day" for non-premium orders so it seems that clock begins the moment the order arrives, even if it comes at 23:59.
So, it's telling me to ship the order by the end of Tuesday!
That wasn't the plan, I wanted Monday and Tuesday to be non-shipping days.
I guess I've answered my own question but in the 12 years I've been selling on Amazon, this is the first time I miscalculated. Fortunately, not a problem.
Next time, I will update the handling time at ASIN level to be sure.
