the sites are still intact to broadcast from though should they need to change back
No they're not. Leicester Sound's studios were ripped out the day after they stopped broadcasting from there.
Northants 96's studios are completely gutted.
Ditto for many others.
sales teams will be moved "on site" to the regional centres this year. I'm fairly sure this was all on one of the leaked Ashley Tabor emails. Radio Today ran it.