Repair Escrow Rules. How can I use this money?

Hello,

Seller has offered to fund repair escrow after closing. They have paperwork entitled "Escrow Agreement for Postponed Improvements" to guarantee they will return money after closing that I can have for reserves in my operating account. Do I have to use this money they "give back" to me in a certain time period? 

Also, do I have to use this money for improvements (maintenance/capex only)? 

Any input/advice would be appreciated. 

Thank-you in advance!