This post in the Documentation Suggestions thread suggests the patch level for 1.2-r stable. also points out it might be best not to try relocking bootloader untils you are sure that eOS patch level is higher than the current patch level you have on device at the moment.
The install document may not be the best place to show the patch level because the links take one to multiple choice of os versions to install! Would be better to show patch level next to the os version on the download page if possible.