際に/際/際は => occasion, time N2
[際「さい」]して/に([際「さい」]し)/に[際「さい」]しての => At the time of A (which starts now).. N2
Time, Situation
放題 => doing as one pleases; to one's heart's content; leaving uncontrolled N1
に際して => on the occasion of; at the time of ~ N2