I already guessed that you, like the "Amill-teachings," do not recognize the distinction between the Greek words (Paul used in this context)...:
-- "eita" (Paul used in 1Cor15:24a "Then [eita] the end"), which is a SEQUENCE WORD ONLY with NO time-element attached (regarding the LISTED ITEMS in this section [note how Jesus' resurrection v.20 was some 2000 YEARS prior to the next one in the LIST];
...so there is NO PROBLEM AT ALL with the LAST ITEM in this LIST to take place 1000 YEARS after the previously-LISTED ITEM in the text... esp. due to this "eita" word [a SEQUENCE WORD ONLY, with NO time-element attached to it])... "eita" used in v.24a (the last listed item)...
--and "EPeita" that Paul had used in the immediately-preceding verse (v.23) ("upon-then" [similar to the way our English term thereupon carries a much closer connection] regarding the LISTED ITEMS in this section [re: resurrection])
-- "eita" (Paul used in 1Cor15:24a "Then [eita] the end"), which is a SEQUENCE WORD ONLY with NO time-element attached (regarding the LISTED ITEMS in this section [note how Jesus' resurrection v.20 was some 2000 YEARS prior to the next one in the LIST];
...so there is NO PROBLEM AT ALL with the LAST ITEM in this LIST to take place 1000 YEARS after the previously-LISTED ITEM in the text... esp. due to this "eita" word [a SEQUENCE WORD ONLY, with NO time-element attached to it])... "eita" used in v.24a (the last listed item)...
--and "EPeita" that Paul had used in the immediately-preceding verse (v.23) ("upon-then" [similar to the way our English term thereupon carries a much closer connection] regarding the LISTED ITEMS in this section [re: resurrection])