End of mourning under review, as exemplified in this clue? (6)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

definition: this clue has “mourning” as an example of a gerund, and perhaps also highlights the “End of mourn- ing “, the -ing form typical of gerunds end letter of [mournin]-G + anagram/”review” of (under)*