It'd be useful to know when and from where accounts were last accessed. If JB was the one who left at 12:30am, or went to bed, or whatever, than it's probable that she accessed some of the accounts after that. If it was SB that left at 12:30am, then that may have been the latest time she accessed the accounts, unless she did from elsewhere, later on, without the phone. Or she came back sometime the next day, when JB wasn't around, and may have accessed accounts up until then, left her phone, and disappeared after. Whatever the circumstances, the access times and method of access would have to jive with JB's story...
If LE had her laptop, they could check the entire history of activity of those days.
Something makes me think the laptop disappeared with her.