If you take the distribution while an IL resident you will pay tax to IL State on this distribution. Since you are going to move to CA, you will file CA part year resident state tax return and you will pay tax on the CA state income. However the manner in which the tax is calculated is based on CA tax on your total federal income and than pro-rated to the CA state income for the year.
Let me know if you have any question.
Please note: This advice is provided with the understanding that all the relevant facts have been provided by you. Any change in facts might affect the advice given and hence may not be relied on in such cases. Nothing contained in this reply was intended or written to be used, can be used by any taxpayer, or may be relied upon or used by any taxpayer for the purposes of avoiding penalties that may be imposed on the taxpayer under the Internal Revenue Code of 1986, as amended.