After attendees to the rock concert event spent hours snarled in traffic, Download Festival's manager issued an apology.
Major delays were reported on the roads around Donington Park in Leicestershire on Wednesday.
John Probyn said organisers were working with the local authority and transport agencies to minimise delays.
Motorists have been told to only follow official travel advice from festival organisers.
The latest advice, according to the festival, is to only use the A50 and junction 24 of the M1.
On Wednesday, National Highways reported "severe delays" affecting the M1, A50, A42, A38 and A453.
More people are expected to head to the festival on Thursday along with thousands of additional day ticket holders.
The festival will be marking its 20th anniversary at the 2023 event.
