[ח' חנוכה, תשי"ח]
...מובן שהארכת זמן החתונה לשנת תשי"ט תהי' גדולה ביותר, ובודאי יהי' כסיומו במכ', באמצע הזמן, ולאחר רגע ההתחלה, לדעת כמה וכמה - אמצע נקרא (ראה תרומות פ"ג מ"ה ובירוש' ומפרשים שם).
B"H, 8th of Chanukah, 5718.
It is understood that extending the time of the wedding into the year 5719 will be extremely significant, and certainly it will be as its conclusion in Makkot, in the middle of the time, and after a moment from the beginning. According to many opinions, 'middle' is defined as such (see Terumot chapter 3 mishnah 5 and in Yerushalmi and commentaries there).
Summary
Delaying an important event like a wedding even briefly can carry great significance. The Rebbe draws on Torah sources to show that even a short extension into a new period is meaningful and should not be underestimated.