anyway for those who're also unsure like me about whether topping up existing unit trusts qualify for multiplier, regardless whether the existing unit trusts were purchased via RSP or lump sum, the answer is yes, for lump sum purchase - it falls under Unit Trust Lump-Sum, not Invest-Saver (so the 6-month redemption, blah blah doesn't apply)..
my B&E summary reflected the lump sum as eligible purchase today.
the CSO who replied wrongly to my query in the digibot message inbox ought to be.. sent for retraining.
Me :
Hi, I have existing XXX funds which I had purchased under RSP that I stopped in Sep 2021. I have not redeemed the units.
Today I purchased more units of the same fund. I would like to confirm that the amount purchased is eligible for the DBS Multiplier bonus interest?
CSO:
Dear Mr XXX,
Thank you for reaching out to us.
The fund will not qualify as a new investment.
...
For the re-purchase to be recognised, the fund has to be terminated and fully redeemed for at least 6 months from the date of termination or date of full redemption, whichever is later. Alternatively, you may consider purchasing a new fund to continue recognition.
it's sad that b&w turns out to be wrong while the other comms (phone, f2f) turns out to be correct.
of course the final 'verdict' was revealed in the B&E summary.
so sometimes CSOs can give wrong answers even if in b&w. I do find that nowadays CSOs across all sectors are rather poorly knowledgeable and can only answer basic, generic questions which are already in FAQs/websites.