answered
2019-03-31 10:50:36 +0200
It would be interesting to know whether the IMSI has a different MCC/MNC from your home network, as that piece about Android I linked to says, but if true what could you do about it?
Presumably your home network's HLR contains these anamalous IMSIs. If this is a valid situation in GSM, which seems likely since it works and other networks on which you roam can locate your home operator, then the fault does lie with Jolla - its definition of, or test for, roaming is too narrow.
What's the correct test? That 'national roaming' proposal in the Android link seems to assume that the anamalous IMSI will have the 'correct' MCC. Is that true? Without knowing why this happens we don't know. I can see 'country' becoming less important in EU mobile infrastructure. OTOH 'allow in-country roaming' might be useful in other circumstances, where an operator has local access agreements, and might (or might not) solve this problem.
Would an alternative, albeit less user-friendly alternative, be to simply specify in settings the home network's MCC/MNC in the case where it's different to the IMSI? Would that be patchable?
Maybe this problem originates from the sale from Orange to A1. Maybe from an in-country access agreement that's become permanent. Maybe not all Yesss SIMs have this 'feature', You could ask them.
Will make this an answer for techical comments.
(I'm in the UK and sometimes have a UK 3 SIM in one slot and a German Lidl/FONIC SIM roaming on O2 in the other.)
I have exactly the same problem with my provider BOB which is also a virtual network of A1 Telekom Austria. Sadly nothing changed despite i have already made a feature request in february --> https://together.jolla.com/question/26151/feature-request-differ-between-national-and-international-data-roaming/
Stefan P ( 2014-07-14 09:59:10 +0200 )editIs there any information on this bug? One could simply make an option to manually select the home network, if otherwise Jolla would be roaming.
renegade22 ( 2014-12-24 14:36:36 +0200 )editI'd never come across this problem despite using several SIMs all over Europe, and wondered what feature of these MVNOs caused it. I found this explanation. https://www.xda-developers.com/android-p-national-roaming-toggle/
DaveRo ( 2019-03-29 23:54:11 +0200 )edit