Porting mobile number from one supplier to the next.

Can some kind person explain exactly what work there is in porting and who is resposible please?

You'll need to ask your current supplier for a PAC - Porting Authorisation Code. Have a read of this..

My wife & I both did this over 2 years ago when we moved from Orange to Giffgaff. We were somewhat apprehensive but it turned out to be very straightforward.

I had a PAC and sent it to Plusnet while ago. they have given me a port date of today. so we will see.

Have moved from EE to Vodafone, to O2. Always been straight forward, at some time during the day you lose your original network then put in new sim and sometime after are on new network.