I started StashAway last month without any referrals. Can I still get the free 6 months management fee waiver if I add a referral from someone else now?

If I want to add a lump sum money into my Stashaway account, is it better to add that in gradually (increase my monthly/weekly DCA by RM X over X months)? Or is now a good time to a dump it all in at once?

For reference, my risk index is 36%.