Seeing perhaps ten per week that fit this theory, plus another 10-20 for exchange only line areas, many near exchanges but others further, i.e. depends on where the cluster to be served is.
The January ISP Forum announced that they were intending to do 2,800 extra cabinets - either to improve speeds for long lines or as extra capacity for in-demand cabinets. Those would be added from 2016 through to 2020/21.
To meet that plan, they'd need to do roughly 10 cabinets per week, so I guess we can expect to see that rate continue for a good while longer.