cipher - The Twenty Doors (ROOM 8)

This is part of The Twenty Doors series.
The previous one is The Twenty Doors (ROOM 7)
The next one is The Twenty Doors (ROOM 9)

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You move on into Room Eight when Kslkgh (a.k.a. Dr. X) finally creates the next room. There is, as always, a slip of paper on the floor:

Before the alphabet, before. The pass, between the alleys. Automatic keying.

Ip wbgft kk tzttfzz, gsx setx kegv pv 'GRIF RRWOJ CUQ RF OYJCXKI' lx ffm lukqyp.

- Jd. Q

And, on the wall, there is... no hint?!
There is no hint for Room Eight. Work it out from the first part of the message - Dr. X

And, finally, you look at the keypad, which is a normal keyboard.

What should you type in to open the door?

The next door will be added when Dr. X comes up with it (if this room is solved)!

Answer

You need to type:

DOOR EIGHT LET ME THROUGH

And the door will let you through (hopefully)!

Explanation:

This is a Vigenere Autokey cipher, which uses a password as well as a modified alphabet. The alphabet you're using puts the word BEFORE before the rest of the alphabet, resulting in BEFORACDGHIJKLMNPQSTUVWXYZ. Then, with a passcode of 'betweenthealleys', we get the result "In order to succeed, you must type in 'DOOR EIGHT LET ME THROUGH' on the keypad. - Dr. X".