Thank you for your reassurance, Amy.   

I've recently found out that if someone calls my work number with a Galaxy S7, my full name apears.  I have emailed Samsung and they told me that is possibly due to the fact that my sim is registered in my name.

A "Lycamobile" phone sim card from any Tesco is completely anonymous, no registration is required to use with all various bundles which are good value such as ?15 per month with unlimited calls, unlimited texts and a certain amount of data, you do need to look carefully for the bundle information as they do like you to register but it's not necessary. It piggybacks on the O2 and 3 network, you can't receive or send mms (pictures via text) but you can use whatsapp for that