On the evening the sheriffs arrived at Puma Path, due to the neighbor's 911 call, they must surely have wanted to talk to the neighbor, but also to household members. About Suzanne's typical whereabouts and what, in fact, triggered the household members to ask the neighbor to dial 911.
My thinking is that LE surely talked to some or all of the household members by phone and early on, it was either established that Suzanne typically biked at a particular time of day - or it was not. If one household member consistently had a different view than the other members, then that would be perplexing.
At any rate, they either established that Suzanne usually went in the morning (thereby making it really odd that she's still gone at 6 pm) or that Suzanne went at various times. Surely, if her typical time was the evening, there would be no cause for alarm? I would expect that the daughters mentioned their attempts to speak to their mother that day.
Isn't the next step to find out if her bike is gone? Surely one of the household members gave LE permission to check for the bike - if in fact, the neighbor had not already been given access. Many garage doors can be opened with a pin code, perhaps the neighbor was given that code on this occasion - or already had it, if the family was so-inclined.
If the neighbor had opened the garage to see if the bike was there, then LE knew it wasn't there. If not, they'd surely ask permission to look in the garage? (From one of the household members? Who are frantic because mom is missing?)
So now, by 7-ish, there have been phone calls among LE and the various family members who instigated the neighbor to dial 911, because otherwise, there's no reason for LE to be there. Whole situation is murkier than it could have been if, say, Suzanne had texted a family member and said, "It's 9 am, I'm skipping online church and going for a nice long bike ride." Or "It's 10 am and church is over - off for my ride!"
If she did those things, then, yes, LE now has good reason to believe she is overdue.
Next: finding the bike. BM's vague statements on TD"s video seem to imply that LE found the bike. Somehow, I thought that was tweeted early on, as well, maybe someone else will remember. LE said that they launched a search of the immediate area that lasted way into the night, and resumed at dawn, with outside help (I think including dogs - different types of dogs over the next 2-3 days).
So, by 9 pm-ish when BM came back to the house, search was underway, LE obviously talked to him - a lot. We have no idea if all of this talking took place inside the house, I'm assuming it did - with BM accompanied at all times by LE, as would seem natural enough as they listened to everything BM said in response to their questions.
At what point household members went to another place to sleep/stay is open to interpretation and debate.
But I doubt that Suzanne's residence was left unattended by LE very frequently - or at all - after May 10, and it is likely that family were politely asked to stay away while the investigation took place. LE said BM was "cooperating."