Is fido.net the network carrier, that you use. There I found this info on compatibility:
So it’s
- GSM, UMTS, HSPA and HSPA+ at 850 MHz and 1900 MHz and
-
LTE one of theses
- 700 MHz on Band 12;
- 1700/2100 MHz on Band 4;
- 2600 MHz on Band 7
Network wise, there is no difference between the Fairphone 3 and 3+. Take a look at the comparison document linked on the FAQ page for Fairphone 3(+)
According to that, the FP3(+) supports both 3G frequencies and the 4G bands 4 and 7, but not 12.
Regarding your general dilemma, I feel for you.
To be honest, though my FP2 is working just fine for years now, it has quite a few design flaws, as it took modularity a step too far. The FP3(+) has been designed in a way to stop such troubles from happening. And it seems, that the main troubles right now are caused by a troublesome OS (update); i. e. Android 10. But that can be fixed; other than design flaws.
Coming by spare parts and the like might be easier for the FP3(+) in the longer run, simply because it is sold in much higher numbers. If I recall it right, they already sold as many Fairphone 3 in the first year, than they sold Fairphone 2 in all 3 years.
And if Fairphone considers shipping overseas (i. e. USA most likely), they hardly won’t ship any FP2 parts. For the FP3(+), there is a (small) chance at least.
But right now, you will always have the problem of importing stuff.
And regarding batteries, that’s especially troublesome to neigh impossible.
Fairphone won’t ship outside the EU; not even for resellers.
Good luck for your support request.
I just fear, they won’t service it, since you are not in the EU; or you will have to pay shipping etc, making it a quite expensive repair.
I really keep my fingers crossed for you.