All East London routes appear up in the air as the Southend service is running through Stratford. I shall be executing bus\tube to Stratford from Blackfen, train to Basilidon and route 100 bus to Chelmsford and reverse in return. If you were going to do the bus out and back to the ground, the day ticket taking in the 100 is not that much more expensive.
Your choice, should you choose to make it, is service bus or replacement bus but, on this occasion, not no bus at all, unless you want to drive!