Why a (Vodacom) LTE APN?

[Mobus]

Can anyone enlighten me why we need to use a different apn for LTE access? Is there a technical requirement or a different apn "protocol" followed to actually facilitate LTE speeds, or is it simply an accounting method to herd all the LTE sheep together?

Can you use the standard "internet" apn or any other apn (ie. the FNB connect apn) whilst the phone is showing a 4G/LTE connection? Will you still get LTE speeds or won't the phone connect at all?

In the latter case, do I have to put the phone in GSM/WCDMA only mode in order to use i.e. my free monthly data via the FNB connect apn?

 

[VC-1]

It has been my understanding based on discussions with senior Vodacom data executives in the last year, wherein they stated that the 'LTE apn' will fold into the 'internet.apn' thus all VC SIM cards will be automatically previsioned for LTE not requiring this special apn. Further to my knowledge that this is the case presently.
Perhaps VodacomData can comment or confirm this. With my phone set to internet.apn it regularly runs on LTE if detected.
Edit: I have noticed that if I use the "internet.apn on a LTE handset it does well on this mode but when mobile between LTE and 3G areas the phone tends to have network issues. Resolving this was to switch the apn to "lte.Vodacom.za".