There was a long discussion about if we show 4G or L - basically saying, that term is not standardized, and was used and abused by vendors, by Google and Apple, in a very confusing way. LTE is used by Apple mostly, while 4G is more used by Android to describe the same thing.
Technically speaking, LTE is not even 4G. Its more like 3.9G since it does not reach the required speed of 1GBit/s in the 4G spectrum. There is a standard called LTE+ or LTE Advanced that would be needed for that.
The speed indicator should therefore show: 2G - G - E - 3G - H- L - 4G in ascending order. But there is one problem: Our interface to the modem does not have an option to detect if we have LTE or LTE-+ speed negotiated. So, best option is to show "L" and you can say thats "at least LTE, but maybe LTE+"