I try to change the SSID VAP name with the vaprename tool. It seems that works, I reboot the raspberry but the VAP name still remain 'astroberry'. I need to change this name because when I go with the telescope there are a lot of people with astroberry and I think that could be a problem.
Good catch! vaprename must be updated to work properly on both 3B and 3B+
In the meantime change the VAP name manually in ALL .conf files located in /etc/hostapd/
You can do this by editing the files e.g. sudo nano /etc/hostapd/hostapd.conf