This was reported by the Institute for the Study of War (ISW).
Earlier, someone from the Russian government mentioned that Wagner's PMС group is in the first step of leaving Belarus. They are moving around 500 to 600 people to different places like the Krasnodar region, Voronezh, and Rostov regions. The second step will start after August 13.
It seems that Wagner's soldiers might be leaving Belarus. This could be because Alexander Lukashenko decided not to pay for them when he found out that Russia wouldn't cover their salaries, which he was probably expecting. But a small number of Wagner trainers will stay in Belarus to help train Belarusian forces.
Right now, experts at ISW haven't seen clear proof of Wagner's forces leaving Belarus. The source mentioned that the fighters who weren't sent to Libya went on a sudden break to Russia on August 6. They have to stay in touch because new orders might come at any time.
On June 27, self-proclaimed President of Belarus Alexander Lukashenko confirmed the arrival of Yevgeny Prigozhin in the country. According to him, Wagner mercenaries who arrived with him will not guard the Russian tactical nuclear weapons deployed there. However, Lukashenko emphasized that he expects the mercenaries to help in the defense of Belarus, without specifying the potential source of the country's perceived threat.
On June 29, a satellite recorded the construction of a tent camp near Asipovichy in the Mogilev region of Belarus, and on July 3, Russian media published a photo of an alleged Wagner camp.
On July 11, the Belarusian Ministry of Defense stated that the Wagner mercenaries would train the Belarusian army.
On August 7, military exercises began in Belarus. The training grounds are near Poland and Lithuania, and between Belarus and Russia's Kaliningrad region.
On August 9, it was reported that Poland will additionally send twice as many troops to the border with Belarus than planned.