Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
because requirements may change at any time , be sure to check for up-to-date information before booking and departure . 

```
. OPTIONS: ['Contract by using' 'Unilateral change' 'Limitation of liability'
 'Arbitration' 'Unilateral termination' 'Content removal' 'None'
 'Jurisdiction' 'Choice of law'].