The Springboks playmaker has been sidelined with a serious knee injury which he sustained in the URC defeat to Leinster at the Aviva Stadium at the end of January.
With just five rounds of action left in the regular season, the Stormers are involved in a tight tussle with several other sides in a bid to advance to the playoffs.
Ahead of Friday's clash with Ulster at Kingspan Stadium, the men from the Cape currently occupy eighth position in the URC standings, but with just eight points between fifth-placed Cardiff and 15th-placed Zebre Parma, there is still plenty to play for in the hunt for the playoffs.
The Stormers started their overseas tour with an impressive bonus-point victory over the Scarlets last week and will look to continue with that form against Ulster, who occupy ninth spot on the table, just a point adrift of them.
Although they are without Libbok at the moment, the Cape Town-based outfit have been boosted by the return from injury of fellow Bok playmakers Sacha Feinberg-Mngomezulu and Damian Willemse, who will start at flyhalf and fullback respectively against Ulster.
And Dobson revealed that he wants Libbok to make a full recovery before he returns to action. After this weekend's action, the URC takes a two-week break as most teams turn their focus to the Champions and Challenge Cup competitions.
"If Sacha [Feinberg-Mngomezulu] can keep going [stay fit] we will keep him [Libbok] on ice," Dobson said. "We could push him into action against Benetton [if needed on April 26].
"With that two-week [European break] we probably look at bringing him back against Cardiff [May 16].
"He could play earlier if we need him."
With Springboks lock and regular skipper Salmaan Moerat ruled out with a foot injury, Neethling Fouche takes over the Stormers captaincy for the Ulster encounter.
Fouche comes into the run-on side at tighthead prop for double World Cup winner Frans Malherbe, who is being rested.
Meanwhile, Willemse replaces the injured Warrick Gelant (knee) at full-back while Dave Ewers comes in on the openside flank for Deon Fourie, who suffered a concussion against the Scarlets.
Dobson is hoping that Moerat, Willemse and Fourie will be available for selection when the Stormers return to action against Connacht on April 18.