You can all make unlimited transfers until the first game kicks off It's standard these days, otherwise they'd get thousands of people trying to enter a team in the one hour before kick off and the website will collapse...
Are you saying pick players from Groups A-D as if they don't get picked you can replace them with players from Groups E-H and get a second bite at the cherry?
Also, without giving away your strategy too much, do you subscribe to the theory that there is no point signing "big" players like Ronaldo, Kane, Messi etc as every other sod will have picked them so you don't really gain any advantage? Or would say these sort of players accompanied by a few dark horses is a better strategy? I could never figure that out with fantasy football.
Say you've got three transfers - You start with Greizman, he plays Friday, you transfer him out on Saturday for Messi, swap him Sunday for Naymar, then swap him Monday for Lukaku. You've had four games from them and Lukaku still has two to come. You've had a total of six games from that one position so you've had an extra game from each transfer.
If you started with someone from Group H there's nowhere to go, anyone you bring in doesn't really gain anything. You always want to be swapping someone who's just played to someone with games to come. They'll be exceptions, you'd rather have someone playing Saudi Arabia than Germany even if you don't gain a game, but you want a majority of your transfers to be swapping to someone in a later group.
On picking the big players - In a Premier League game there are always some players you have to have (eg. last season Kane and Salah) but at a tournament not so much. I'm not considering Kane or Ronaldo. I doubt anyone will score so big you can't manage without them. It'll probably come down more to having the right defenders......
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