Calling 999 when you don't have a phone signal?

I've never had to do this but I have wondered about it ... it still might be possible:

• Your phone will use any available network for emergency calls, even if your phone is showing no reception on your usual network.
• Texts often get through even when reception is too poor to make a voice call.  You can make a 999 call by text, if you have registered in advance.  See below.
• It's recommended to have the What3Words app on your phone.   This gives you a three-word code for your location - for example ///tour.spark.large.  This can be used by the emergency services to find you.
• Finally, it's a good idea to have your emergency contact details with you - in your wallet, on your phone (which the emergency services can access by the way), and registered with the club.

This web page gives more details: https://1firstaid1.co.uk/calling-999-with-no-phone-signal/.

I hope this information proves to be completely useless to you!