Samsung Galaxy S4 — Samsung S4 (SM-S975L)

Hi team

The phone I have is the Samsung S4 model SM-S975L and if I switch it on it shows Tracfone and my service provider is Net10.

My question is, where can I find firmware updates (if any) for this device as most, if not all, updates are for other models on the bigger networks?

Thanks in advance.

So I contact Samsung regarding an update and they say contact Straight Talk. Straight Talk say contact Samsung.