I would continue to use the Delta and Hilton cards quite heavily, pay once per month, for about 6 more months.
Then just app the BCE if that is what you want.
Keep in mind AMEX does not like churners, so keeping these cards a couple years is advisable. Those who start a pattern of getting SUB, then closing AMEX cards are now finding disappointment on other SUB apps.
High Bal Jan 2009 $116k on $146k limits 80% Util.
Oct 2014 $46k on $127k 36% util EQ 722 TU 727 EX 727
April 2018 $18k on $344k 5% util EQ 806 TU 810 EX 812
Jan 2019 $7.6k on $360k EQ 832 TU 839 EX 831
March 2021 $33k on $312k EQ 796 TU 798 EX 801
May 2021 Paid all Installments and Mortgages, one new Mortgage EQ 761 TY 774 EX 777
April 2022 EQ=811 TU=807 EX=805 - TU VS 3.0 765