There are a number of future forms: The party will start at 10 pm The party'll start at 10 pm The party will be starting at 10 pm The party'll be starting at 10 pm The party is to start at 10 pm The party's to start at 10 pm The party is starting at 10 pm The party's starting at 10 pm The party starts at 10 pm The party is going to start at 10 pm The party's going to start at 10 pm The party's gonna start at 10 pm And I don't think 'going to' is the right form; it is too assertive. I have bolded the one I suggest as a less formal version of the first one in the list. Welcome to English Forums, Bob.
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