Good question! I did check that and they do have enough. Following the system reboot, the phones started to register (apart from one which was set to another country).
So all OK again thank you!
But just as was about to leave they came out with another issue, that of "handshake problems" when walking about the hotel. They have about 40 Samsung WEA302i APs and one WEC8050 controller. I will have to go back in on another day for that. Although I did have a hand in the installation, Samsung UK were responsible for it and did all the config.
This was about 5 years ago, so most of the APs are that old. I am thinking that these APs may suffer over time, like their antennas must depreciate a little over a period of time?

Mike