While Thunderstruck will run for a week, Mode Mastery will persist through the entire Season 3 of EA FC 25, so you'll have plenty of chances to grab the Mode Mastery players. As per EA ...
With the second week of the Fantasy FC promo arriving soon in Ultimate Team, leaker @FUT_scoreboard claimed the EA FC 25 Conor Gallagher Fantasy FC SBC will be released soon as well.