Inconsistently.
Jane's network has kept all the Bells' worlds - and every other world with a Janepoint stuck in due to its being attached to Downside - in temporal sync, but when Jane spluttered for just a moment, that was shot to hell.
Peace lost three seconds, because it was where Aegis torched; after that process was complete, Jane was there again. And as soon as a door between Peace and Milliways appeared, she could sync to her ansible hub in the Belltower and, from there, to everywhere else.
Atlantis and Sunshine each stand at about a minute apiece: Shell Bell's aura and Juliet's local copy of Jarvis both enabled them to get to Milliways immediately, pausing their homeworlds as standard for occasions when someone walks into the bar. Shell Bell's the one who connected Peace.
Everyone else was running on luck.
Luckiest is Rainbow, which lost only five hours.
Next is Alethia; in spite of Sherlock's mishap, it's fared reasonably well, spending only six weeks isolated.
Syntropy's just a little worse - seven weeks.
Origin waited two months.
Eos waited three.
Thilanushinyel, ten.
Everyone else is out a decade at least. Samaria's ten years, almost ten and a half.
Aurum is out eleven.
RĂªverie has been separated for sixteen years.
All the Bells - and Elspeth, who was stuck in Downside for a day and a half on her end and whose mother was very upset - are collected in the Belltower, as are two Bell-attached Sherlocks who happened to be along for the ride. They all memorize this list of numbers. Aegis replaces her earpiece. And then they all go home to notify their loved ones and staff that there's a party cooking in the Belltower.
(Shell Bell, who has no particular cause on her own account to be distressed, sends her Sherlock to invite Tony in while she refits the Belltower to suit a party of a peal of Bells and their larger-than-last-encountered families and circles of friends.)
[So maybe not a Bell after all, unless the building was serving another function... What about non-house places? I know Aegis is planning to set up a station with a space elevator in it to process dead people and send them home. How would you feel about being a space station? With living quarters in it for Aegis and Sue but not necessarily them in it too often.]
[There's not good data on it, but all the Sunshine-type worlds plus Yggdrasil show the same time. My clock in the Belltower matched Sunshine after Juliet opened a door; my clock in Atlantis matched when Shell Bell came in, and once the Belltower clocked snapped to my clock in Peace I was awake again and had all my stuff back. If Peace and the Belltower had never unsynced I think I wouldn't have lost hold of it.]
[Guess so. They seem to be working on making sure Aegis never torches again, though. People keep wandering by to lay more wishes and enchantments on her. Sarion cooked up something elfmagey, and Amariah gave her a complement of cloudpine-witch spells and tattoos, and Cam spoke a bunch of wizard wards for her, and Aurora's going to do something sorcerous once Brilliance is available to help her with it, too.]