How far in advance of receiving an installment payment for an enlistment bonus will it appear on an LES?

CSM Darieus ZaGara is correct. Your installment payment will show on your next LES for release in your account. It is usually the anniversary LES of your bonus date. If the bonus is to be paid after the 1st of the month, it will show on the 15th LES and vice versa. So think of your bonus anniversary date, when it is and what is the next LES pay date.

Have u received it yet?

You generally see the payment the month it will be released to your account. Thank you for your service.