Special instruction ESUs for canadian payroll

Hello there

We never had any ESU install since last year ESU in Feb 2011.
I am wondering there are some ESU which i need to apply for this year but has some prerequiste but the date for those SAR/BUGS in the prerequistic ESU is old e.g 2006 i assume i just need to follow only those special instruction which belongs after Feb 2011.?

I use change assisstant.

Thanks
AD

Change Assistant will provide the baseline ESUs and other ESUs that are the requisite for your current release level. YOur current release level will have included earlier ESUs that have been incorporated into your release.

Thanks AL.