Hello Flick and welcome to the forum!
The Corporation roadworks are done overnight. During the day they only do absolutely necessary repairs. During the daytime, they’ll park the road repair vehicles somewhere, rather than take them back to the depot. All of that makes sense. What annoys me, too, is that they park these vehicles etc in the suspended bike bays, of which there really aren’t enough in the City. The reason is pure & simple: money. We don’t pay for the parking, cars do, so the City won’t suspend car bays. They park the vehicles in the nearest bike bays big enough to accommodate them, so it might be that the roadworks were actually half a mile away from the bays, explaining why you didn’t see any.
As for the ticketing the scooter is concerned, there should be 24h notice. Normally there’s a notice from the Corporation on a lamp post or on a movable post saying that the bay will be suspended between these hours during these days. It should definitely have been there the previous evening, but of course the scooterist was unfortunate, and left it there the previous morning and either didn’t see the notice, or it wasn’t there yet.
Bays are suspended very frequently, as the Corp has launched a massive road surfacing programme, so please check your bike is not parked in a bay about to be suspended. If you know you’ll have to leave it there overnight, when you leave the office swing by your bike to check the bay hasn’t been given a suspension notice.
The bike bays in the Corporation area have a non-overnight policy, anyway, so the scooter shouldn’t have been left there. I have asked the Corp about this before, as I wanted to leave my bike at the Liverpool St Stn for a long weekend, in case the policy meant I was going to be getting tickets. They said there is no ticketing policy overnight, the reason the bikes are not for overnight stays are the risks of theft (the City being deserted overnight and weekends), and the other current risks for us: suspension due to roadworks and suspension due to security alerts. What they tend to do is, instead of ticketing the bikes in suspended bays, is to move them to a nearby bike bay. Allegedly, if there’s no room in a nearby bay, they’ll move it next to the bay and put a notice saying it’s been moved there by the Corp so you shouldn’t get a ticket. I’ve yet to test this theory.
Therefore, if your bike disappears from its bay during a weekend, call the Corporation as well to check if they’ve moved your bike around the corner.
General advice to people parking bikes in the City: all parking attendants carry digital cameras and will take photos of the bike on double yellows, etc, so you can’t get away with claiming the bike wasn’t parked where it was.
I’m not quite that new to biking though, I had my little SR125 since last Christmas but it was nicked by the good people of sunny Tottenham, about a month ago 
