When I performed pasaload from my old Smart SIM to my Smart Bro plugit, I also receive this info as part of the confirmation SMS.
Smart Buddy's P2.00/min calls. Dial *2222+11digit Smart/TNT/Red#That means Smart subscribers can still squeeze a one- minute call (to Smart/TNT/Red Mobile subscribers) right up to his/her last 2 peso prepaid load.
There was no mention of maintaining balance or duration of this promo.
Feel free to share your experience using this Smart promo. :)