The Silverstone-based squad started the year as Red Bull's main challenger but has since had to face an increased threat from Mercedes, Ferrari and McLaren which have all made good gains during the campaign.
A recent dip in form was blamed on the side effects of an upgrade path that the team took, but Motorsport.com also reported recently that the squad could have been hit by an FIA flexi wing clampdown that is understood to have impacted several outfits.
