I tend to agree with you ladies, if this was the case why was she getting narky at the police so early in the day.
Sending the children off to school at eight o'clock was a way to get rid of them. Lots of schools don't accept responsibility for student prior to 8.20am. I would have thought the little girls would have been getting anxious and upset by about 8am and the better choice would have been to drop them over to Grandma and have play with their cousins. really the more you thinks about the haste that the incident went from Allison having an early morning walk to a murder investigation was less than 2 hours> Something is really not making sense - why did Gerard have to ring the police so early, he could have told the girls that Mummy had left early for the conference, taken the children to school and then had any number of hours to concoct a better story and to tie up lots of loose ends.
His story could have been that he slept later than usual and when he woke he thought that Allison had left for the seminar, then about 10 o'clock he could have phoned her to see how it was going, phone to message bank, the normal thought would be still in the conference, lunch another try and then more regularly in the afternoon. He could have told the girl that was going with her that she had early and must travelled alone. The other lady at the conference would have given her until morning tea or after, and depending on the type of person she was, may have rung GBC at lunchtime. Really he then had until after picking the girls up, to pretend he was concerned. He could have rung the police around 5 and that would have given him a whole day, it was the weekend then and things won't have ramped up until Monday. Very badly thought out I think.
I also think OW laid out the cups and saucers, thinking neighbours would be calling by to offer help and comfort. Bring out the best china for funerals and wakes.