Bill Edgar's Thursday trivia question

Question - Which club, then in the fourth tier, had to apply for re-election to the Football League (they were successful) just six years after playing in the top flight? 

Come back tomorrow for the answer.

Yesterday we asked you: Barcelona have enjoyed the longest current unbroken stretch of participation in European football, which stands at 50 campaigns (the first two of which were the elongated Fairs Cup tournaments of 1955-58 and 1958-60). Which club has the second longest current unbroken stretch?

Answer: Anderlecht (44 seasons).