Sylvie went throughout the alternate timelines, ambushing Minutemen on their missions, and stealing their reset charges. She collected several reset charges and placed them throughout Roxxcart Mall in Haven Hills, Alabama in the year 2050. When Sylvie was found by Loki, she used a TemPad to send the reset charges through Timedoors to several alternate timelines, in order to disrupt the Sacred Timeline.
"When we prune a branched reality, it's impossible to destroy all of its matter. So we move it to a place on the timeline where it won't continue growing. Basically, the branched timeline isn't reset. It's transferred."