FlyerTalk Evangelist
Join Date: Nov 2018
Location: Istanbul, Turkey
Programs: TK Elite Plus,BAEC GGL,ITA Executive, AFKL Gold,QR Gold,HH Diamond,Bonvoy Gold,ALL Gold
Posts: 14,185
Yes, if you decide to reissue/transfer your ticket to flight credit, you could use the Elite Plus vouchers only if there is 'J' fare bucket available on the flights that you would rebook.
Same for award tickets, 'X' or 'I' fare class should be available.
Only, in case of an IRROPS, your flight has been canceled is within the next 15 days, you could ask for extended help at one of the sales offices and during this chaos, the only way to reach them is to go to their office and wait for your turn.