when making a siyum, does one have to leave over some of the last amud until the siyum.
If yes, does that mean he can't prepare it in advance?
Or is there certain amount of time he can prepare it in advance? If yes, how much time?
Answer
One should leave the final part for the actual Siyum, although one may prepare it in advance.
עי' שו"ת שבט הקהתי ח"ב סי' קעא