'a little bit earlier' is a correct and usable phrase in written English. It is typically used to describe a time that has passed before a certain point in time, or a situation that has occurred before something else. Example: "I arrived at the party a little bit earlier than expected.".
We're ending a little bit earlier.
I have to get up a little bit earlier.
"Hopefully we're a little bit earlier in the process".
Vesnina said that the Russian federation could have picked the team "a little bit earlier".
"Our Monday mornings start a little bit earlier," Mr. Esteves said.
"They implemented everything we told them," Klinsmann said, "except maybe scoring a little bit earlier".
[The league] probably can attract some players a little bit earlier, probably 29, 30 years old.
Being a terminologist, I care about word choice. Ludwig simply helps me pick the best words for any translation. Five stars!
Maria Pia Montoro
Terminologist and Q/A Analyst @ Translation Centre for the Bodies of the European Union