Best strategy, attack mode or rules for certain password structure

[atom]

Yes, that's simple.
1. First create a wordlist to match the CBA321: mp64.bin ?u?u?u?d?d?d -o wordlist.txt
2. Run hashcat as normal and add a rule "-j lMu4", ex: hashcat64.bin -m 6211 -w 3 tc.header -j lMu4 wordlist.txt