OK
It appears ALL the tech gurus have emigrated
SO
I looked up -- "Dual Sim"
Seems there are a couple of variants of how this works
This explains
Dual Sim Explained
( Scroll down )
Dual Sim standby and Dual Sim active
Therefore, chip makers like Qualcomm and MediaTek demoed dual 4G LTE last year, and the feature is now a mainstay on phones sold in 2018. As the name suggests, dual 4G LTE enables 4G connectivity on both SIM cards, allowing you to switch between two 4G networks seamlessly.
Dual 4G VoLTE is a subset of the feature, and it allows you to make HD calls from either SIM. So if you have two SIM cards and both facilitate VoLTE, you can choose from either carrier before making a call. Dual 4G LTE relies on Dual SIM Dual Standby, which uses a single transceiver but lets both SIMs be active, facilitating better battery life.
Dual Sim 4G LTE
OK
So this feature IS available ..........
Now
I know I definitely had Dual Sim 4G LTE on my phone as the on screen display showed both Sim cards as having 4G
Which it does not show now -- currently battery life is also a lot better ( longer ) a clear indication of single 4G usage
I have NO idea how it came about that this feature was enabled on my phone ?
As a newcomer to smartphones it was something I never really paid attention to.
I can only thing that out of the various Beta ROMS ( Chinese as well ) I installed there was something that "switched" this feature on
I want it back -- PLEASE ...