Although SERE is a combat support AFSC and is not designated as a Battlefield Airman AFSC it has duty positions that can be generally a M-F day job. But generally it is difficult to hang hat on the majority of duty positions being that way.
Think about, the SERE environment students are being exposed to does not have any time outs. It is 24-7 from time such environment is entered into and gotten out of. The field portions of SERE training of a SERE course does not stop for coffee breaks or because the union whistle blows for shift change on the assembly line.
There is a set schedule for the instructor, but its governed by when a Course class starts training day one and ends with the last training day of the course.
Further SERE inherited from Life Support (now aircrew flight equipment, AFSC 1P0X1) all the local base SERE continuation training given to aircrew and care and feeding of those play survivor in the field in such exercises as Red Flag. Thus there are TDYs.
SERE also inherited from intel ISOPREP and other Personnel Recovery (PR) operational support responsibilities such as debriefing repatriated isolated personnel.
As SERE duty positions are only one, two and maybe three person deep buried in the Wing level organization it can be a easy day or a very busy day.
I am not aware of the AF Reserves operating any formal SERE course. AFRES SERE may be supplying/augmenting SERE Instructors at the AETC SERE courses, but the primary purpose for AFRES SERE and ANG SERE is to pick up and do those training and PR Operational Support duties that used to be done by life support and intel personnel. AFI 16 1301 SURVIVAL, EVASION, RESISTANCE, AND ESCAPE (SERE) PROGRAM
Read Chapter 3 - Operational Support and Chapter 2 - Code of Conduct Continuation Training.