Do all applicants who are accepted receive a provisional admission contact or is it only select ones?
I copied and pasted the contract below here
Because your admission has been based on the information you reported in your University of California application and/or by written/ verbal communication with our office, we expect that you will do the following:
Maintain Academic Performance
Complete your senior year program with the same high standards you have demonstrated thus far. You must complete the senior year academic classes listed on your application with at least a minimum overall unweighted B average.
You must notify our office if, in your senior year, you receive two or more C grades; you receive any D or F grades; or your class schedule changes. [See Contacting UCLA.]
Send Official Transcripts
Graduate from high school and arrange for your school to send us a final, official transcript that confirms your date of graduation and verifies the academic information you reported on your application.
Send Official Test Score Reports
If you have not already done so, have official reports of your ACT/SAT exam results sent to our office. Visit A Student Site for ACT Test Takers | ACT Student
[UCLA's ACT code is 0448] or College Admissions - SAT - University & College Search Tool
[UCLA's ETS code is 004837].
AP/IB/SAT Subject Tests
Have official score reports of results for any SAT subject tests or AP/IB tests you reported on your application sent to our office. Contact College Board for AP at 609.771.7300 or SAT at 212.713.7789 [UCLAs ETS code is 004837]; or IB at 301.202.3000.
Comply with Deadlines
Our office must receive all the required official documents by July 1, 2013. If your transcript and test scores are not received by July 15, 2013, a hold will be placed on your record. This will prevent you from enrolling in classes and receiving services from the university.
Submit your Statement of Intent to Register (SIR)
If you intend to enroll at UCLA, you must accept our admission offer [and submit a nonrefundable $100 advance registration deposit, if required] by May 1, 2013.* To do this, visit the New Bruins website at New Bruins - Freshman New Student Checklist - UCLA Undergraduate Admissions
By submitting the Statement of Intent to Register [SIR], you certify that you understand and agree to comply with all the conditions of the contract.
* If you are admitted close to or after this deadline, you will have one  week from the date of your letter of admission to accept.
Please let me know. thanks