Received an offer. Waiting on background check. How in depth is it in terms of your employment history?

I had one job 11 years ago that spanned 2.5 years. However, I left and came back during that time, so there’s a 6 month gap in the middle where I worked somewhere else. That other job wasn’t relevant so my resume shows 2.5 consecutive years at the relevant job. Will this screw me?