Hmmm. Not round here, they're not - far from it!
And 'changed slowly' really isn't good enough.
When they've not been changed, there needs to be a warning well before the problem barrier, so that a different route can be selected if necessary.
The last few evil squeeze barriers are finally slowly going from around King's Lynn, even the fake "it's to stop motorbikes" ones which have injured cyclists (especially older e-bike users with wide/high handlebars) far more than they stopped motorcyclists, because they stopped no motorcyclists. Even the rare barriers set narrow enough to hinder a motorbike, that also blocked mobility scooters and larger wheelchairs, the motorcyclists either took it as a fun challenge to "walk" the bike through on its back wheel, or they simply powered through a drainage ditch in a way few cyclists ever could, or they used another completely unbarriered entrance, such as (in one example) the entrance from a car park! Which was not much help to cyclists because it was in a direction that wasn't helpful for many through journeys... only good if you wanted to get in and ride circles into the playing field.
I suggest that now is a good time to embarrass slower councils into action, by asking Public Questions at meetings about why they're being slow to enable access for all, and by asking if they're not worried about the threat to their funding from their failure to take such a simple measure to support Active Travel.
Even so, there should be a nationwide "removing the barriers" programme, backed by both funding and enforcement of the legal duty for councils not to fark over users with disabilities. Maybe you could write to your MP to suggest it?
www.WriteToThem.com
And yes, where a barrier remains, it should be clearly signed at the last reasonable exit onto an alternative route. There are already standard signs for width restrictions: