Salam.Alaikum....during 10th zil hajj the haji must sacrifice before shaving/triming his hair or getting halal from ihram.... but all campaigns must wait for their turn for sacrifice because there is not just one person or one campaign.... so the campaign lets their haji get Halal from ihram before the sacrifice.....is it right? Or the hajji should wait for thr sacrifice even his sacrifice is done by the last day ? Please understand my question before answering ....
Taking off Ihram is not related with slaughtering or sacrifice. Once you've performed the throwing of stones of Jamrat al-'Aqabah and shortened (for men and women) or shaved (for men on only) your hair, you are allowed to take off the Ihram tissue or clothes! At this point one may do anything which was not allowed while wearing Ihram except having intercourse ...
...Umar ibn al-Khattab said, "When someone has stoned the jamra and shaved his head or cut off some of his hair and sacrificed an animal, whatever was haram for him becomes halal, except women and scent, (which remain haram for him) until he has done tawaf of the House." (Muwatta' Malik)
This tradition may strengthen the hadith which is considered by many scholars having weaknesses:
When one of you throws pebbles at the last jamrah (Jamrat al-Aqabah), everything becomes lawful for him except women (sexual intercourse). (sunan Abi Dawod, sunan ibn Majah, sunan an-Nasa'i and Musnad Ahmad, at-Tirdmihi quoted it in the discussion of this hadith)
Here some fatwas of Imam Malik from his al-Muwatta':
Malik said, "I have heard the people of knowledge say that there is no harm in someone who is in ihram rubbing his head with certain kinds of plants after he has stoned the Jamrat al-Aqaba but before he has shaved his head, because once he has finished stoning the Jamrat al-Aqaba it is halal for him to kill lice, to shave his head, to clean himself of body hair, and to wear normal clothes." (al-Muwatta')
Malik said, "No-one is permitted to shave his head until he has killed his sacrificial animal, and no-one must sacrifice before dawn on the day of sacrifice. The things that should be done on the day of sacrifice are slaughtering, donning clothes, grooming the body generally (at-tafath) and shaving the head, and none of this may be done before the day of sacrifice." (al-Muwatta')
In the maliki madhhab for example it is wajib to perform the "Stoning" before shorteneing your hair (see for example here). BTW they also say that it is possible to pay one of many Saudi "charity" associations -in advance- to do the sacrifice for you and they will spent it in your name. Which will take away from you the burden to wait etc.
ويحصل التحلل الأول باثنين من الثلاثة, فأي اثنين منها أتى بهما حصل التحلل الأول، سواء كان رمياً وحلقاً، أو رمياً وطوافاً, أو طوافاً وحلقاً، ويحصل التحلل الثاني بالعمل الباقي من الثلاثة
This is my own translation of the text (take it with the necessary care):
This basically means that there are two kinds or parts of tahlul leaving the ihram, but not being allowed to have intercourse yet and being free to do anything. and the first part of tahlul "taking off ihram without being allowed to have intercourse" is allowed if two three things have been performed (no matter which two these three) may they be stoning and shaving or stoning and tawaf or tawaf and shaving, the second or full tahlul only is reached when all these three have been performed.
Note that only hajj requires two steps of tahlul or tahlil, while for 'Umrah only one is required!