I am not sifu..

Yes, you can go to the bank only by yourself (since all 5 FDs are either one to sign) to combine
the 5 FDs into 1 FD.
But do it only when all the 5 FDs are matured if you do not want to lose interest.

Also, you need to know if the bank requires fresh fund or not when you renew your
FDs (combine and renew from 5 FDs into 1 FD).

For most FD promo, Banks will usually require fresh fund.

The bank (only the particular branch where your placed your FD) will keep your FD account record
for both of you. Next time, either one of you can go to the particular branch to place or withdraw FD.

If my bonus saver due on 5th june, withdraw using bankers cheque. Does it consider a fresh fund if I bank in the cheque back to OCBC for another 3 months bonus saver? Or i need to bank the cheque into another bank and issue a other cheque to OCBC?