Which is the reversible segment in «وَرَبَّكَ فَكَبِّرْ»?

Qalb, Tashrīʿ and Luzūm Mā Lā Yalzam: Completing the Verbal Ornaments

• The initial wāw must also belong to the palindrome
• Only “fa-kabbir” is reversible
• The entire verse including vowel signs reverses identically
• «رَبَّكَ فَكَبِّرْ» apart from the leading wāw