However the opening of this section was delayed due to the collapse of the Loddon Viaduct on 24 October 1972,[3] which killed three people and injured ten others.

The section of Berkshire Way (and the construction of the flyover) came some years later, allowing traffic to flow from Reading and the M4 past the official end of the motorway onto the Southern and Western industrial areas of Bracknell.

In the early nineties, the section of the A329(M) that met the A4 east of Reading was downgraded to an A road to enable the hard shoulder to be used by a park-and-ride bus service.

The cross-section of the motorway was built in this way to support future widening to dual-three lane standard, which was never introduced: the later southern section to Amen Corner lacks this provision.

In 2006, on an area to the south of the A329(M) just beyond the actual designated motorway section, construction began on a new housing development—Jennett's Park.

The Bragg report considered why this happened and made recommendations as to how formwork should be designed and tested, to make bridge construction safer.