Continuing to buy SBD and reducing the supply by converting it is enough to increase the price. This has been demonstrated numerous times in the past.
The probem now is simply too much SBD in circulation because it was ignored for a long while. If @sbdpotato had started earlier there is a good chance it would already be back at $1.
RE: SBD Potato Day 53: Make SBD $1 Again!