Does the UK not have its own SIM cards that just charge for calls and texts?While you mention it, I have an "Aldi" Sim card from Germany still in my phone since 3 years and it works fine. I have a Blackview BV9000 Pro rugged phone with 3 SIM slots and no contract (of course, because I bought it online direct from Hongkong for 150 quid) So I left the SIM in there and just tested it a few minutes ago... still got 6 € load.
btw... not that I want to advertise, but my phone has done great service in the outdoor, it fell down a couple of time, was submerged in water for many minutes, stepped on, left in the cold and heat, went sailing with me (that's probably the hardest test of all) and its still running fine, only the battery is a bit less now, but I ordered a new one already for 15 Quid and will install it myself when the old one becomes unbearable. because - The phone has screws !!! Believe it or not, one can open it with 16 screws at the back ! And the battery came with an O-ring as well. But probably that's good for another thread to open...
I have got so used to them here , I spend about 5 Euros for 1 month's of calls and texts on my smartphone, SIM from Aldi....... Whatsapp only at home on the WLAN.
Generally speaking, for a GPS tracker, which one hopes will never be used "in anger", why do some people want to buy a "clump" of a device, with only one type of SIM, fixed inside, and pay a monthly rental as well?
Getting a bike stolen once a year is excessive I feel......then it may be worthwhile.... I have had e-bikes over 10 years now, with an alarm and a chain(s), and up to now none have been stolen! 10 years at 24 pounds a year, is 240 pounds, and nothing happened.....
The GPS Tracker offerings on ebay are very varied in price and size, not one to fit all, but everyone should buy what they want.....their own choice of course....
By the way, that sounds like a good phone if it can handle all that misuse.....
regards
Andy