‘The Salaf would supplicate to Allâh, the Mighty, six months before Ramadan that He should make them witness Ramadan, and for six month after, they would supplicate to Him that He should accept their acts in Ramadan.’

Mualiyy bn al-Fadl, Latâif al-Ma’ârif p.156
as cited in An’wâr Al-Bayân p.8