When I search with the / Normal-mode command:
/\\vSEARCHTERM
Vim starts the search from the cursor position and continues downwa
You are already using a range, %, which is short hand for 1,$ meaning the entire file. To go from the current line to the end you use .,$. The period means current line and $ means the last line. So the command would be:
:.,$s/\vBEFORE/AFTER/gc
But the . or current line can be assumed therefore can be removed:
:,$s/\vBEFORE/AFTER/gc
For more help see
:h range