@Marie It appears that Asana → Google Calendar synching is a one-time event, based on all the user reports above. The guidance about 24 hour latency doesn’t appear correct. I’m testing it myself now and will let you know.
The Asana help screens for this also mention " * Completed tasks will not sync". It has taken me 18 seconds to determine that this is not correct. All my completed tasks have synched instantaneously, along with the incompletes, the first time I added my Asana “My Tasks” to my Google calendar.
I understand SW dev takes a while, but I would hope that fixing the help screens to reflect the actual installed behavior should be fairly fast.