Hi again!

I know, you're sick & tired of my questions, but...
Last night I cut my double width tartan into two pieces and put the chalk marks. I found out that one half of fabric is showing some strange behavior. Maybe it was packed on bolt this way, who knows? When I fold it on half (lenghtwise) and match the stripes of tartan it's not folded flat. Like it would be a bit skewed and wrinkled.

I hope this will be resolved during sewing?!?! Any suggestions or similar experiences?