Do I have to reschedule a mandatory SFL TAP appointment?

Long story short I ets in 5 months and go on term leave in 3 months. I scheduled this appointment a month in advance and my leadership is now telling me to cancel my appointment for our battalion field. The major issue I’m having is that the next available appointment for this class is a month and a half away and I work for the brigade clinic so me cancelling these appointments not only means I’m prolonging myself from figuring my shit out before I get out but also it’s affecting the 80+ soldiers I see a week. I’m just trying to get advice on a route to go or if there’s a regulation out there that basically tells me to suck it up and move forward. Thanks in advance.