Successful Administrative Review but cas expires

Dear All,

I have been silent reader of this forum. This helped a lot to prepare my case. I need your valuable advice on my matter. My course was due to start in January 2015. I got visa refusal on 10/01/2015. I applied for administrative review. Its been successful now. They have asked for the passport and valid cas. The next course start date is Sep 2015. University can only issue cas in June (earliest). Can I wait until then? Will that expire this successful review? Or do I have to apply again? I am bit confused. Following is the letter which they sent me:

With reference to your application(s) for entry clearance please go to your nearest Gerry's
International Visa Application Centre on any working day with the exception of public
holidays for the submission of your passport(s).
We are able to post date visit visas for up to three months so it is important, therefore, that
you contact us as soon as possible even if you do not intend to travel straight away.
When you attend the Gerry's International Visa Application Centre, please bring with you:
This letter. Your passport will not be accepted at the UK Visa Application Centre if you
fail to present this letter.
Your passport and the passport(s) of any member of your family detailed above.
Depending on the category of visa you are applying for, there are other requirements:
For vistors
Please confirm your intended date of travel and length of stay.
For students
Evidence of a valid Certificate for Accecptance of Studies (CAS) and course
enrollement date. If your CAS is no longer valid or your latest course start date has
passed, you should contact your educational sponsor as soon as possible and obtain
new course start dates. If you do not do this or your educational sponsor cannot enroll
you at a later date, we cannot issue you a visa.
If you have been accepted to study externally for a degree at a private education
institution, you must also be registered as an external student with the UK degree
awarding body and provide evidence of your registration.
You should also submit all educational documents used to obtain the CAS letter.
Please note if the start date of your course is more than 3 months away, you should
wait until 3 months before the start of your course to submit your passport and
acceptance letter. We cannot process student visas more than 3 months in advance.
For work-based migrants (PBS)
Evidence that your job offer via your Confirmation of Sponsorship (COS) is still valid.
For family migrants
For Settlement applicants please provide a copy of your sponsors passport showing
their current valid UK immigration status.
If you are under 18
If you intend to travel unaccompanied, we require written permission from both
parent(s)/guardians that you may travel alone.
If you intend to travel accompanied by your parent/s, we require the accompanying
adult's passport number and name in full.
If you intend to travel accompanied by anyone other than your parent(s)/guardian, you
must provide written permission from your parent(s)/guardian that you may travel.
TB certificate – please note
If you are planning to go to the UK for 6 months or more you are required to hold valid
TB certificate. The TB certificate is only acceptable if it is issued by the International
Organization for Migration (IOM). More details about TB testing and how to book an
appointment with the IOM can be found on our website
http://www.ukba.homeoffice.gov.uk/count ... tbtesting/?
langname=null
Once your visa application is concluded, we will return your passport(s) and documents to
Gerry’s who will notify you when they are ready for collection.
Yours sincerely,
UK Visas and Immigration

To answer my own question after a little research I think I can hand my passport in June not earlier than that. Does anybody knows how much approximately time they will take to return the documents back to me after that?