The Reuters report says that this in part efforts to move attention away from the events in Downing Street as of late, as Boris Johnson looks to reset his agenda after coming under fire over the party he attended during lockdown in 2020.
The removal of "Plan B" would appease many in the Tory party, so perhaps that is what Johnson is angling towards to try and win back some support. The source cited in the report says that the review could come this week but possibly early next week.