The first criterion is whether or not an exemption certificate is presented to the distributor. If the distributor delivers fuel to a service station, the service station doesn't present an exemption certificate. Knowing this, the distributor will determine its selling price taking into account that the customer will have to pay the fee on the fuel that will be delivered to the service station. However, for a delivery of fuel to a farmer's farm, I presume that the farmer will call the distributor in advance and say that he will present a certificate of exemption. The price can be established this way.
On May 1st, 2018. See this statement in context.