Release notes:

MUX_2.0_by_KINGSEBO (380 M33 proofed)

You need more PSP/GAME/UPDATE Folders.

Use MUX20:

MUX20 Multiplex your Update-folder.

IN PSP/GAME/MUX20/ you have now 9 Update_X Folders.

Put Update Data inside this folders.
Start MUX20
choose your update_x folder an press O to make a notice like: CFW 3.80 M33-1 or 3.80 M33-2 Update etc….

then choose your Update_x Folder an press X. All Files copy to PSP/GAME/UPDATE, so you can start your aktivated UPDATE over XMB like a normal UPDATE.
After Updating you can delete the UPDATE in the XMB, because you can aktivate it over MUX20 whenever you want, and you have no UPDATE-ICON in XMB.

When runnig MUX20 the first time, the UPDATE folder will backuped to ms0:UPDATE_BACKUP, so you don´t lose data.
Credits to:
Dark_ALeX, psp2dev, bumuckle, Team3GO ,smokescreen, QJ, BUM BUMMANIAC, Ralf Richter, Murat, Maria and Peter….