You could make a macro!
Steps:
- Use a find string with wildcards for the variables (if the variable is a cell reference as in your example 'H157' all you need is a single asterisk '*' in place AND you need to ensure that you are searching the values NOT formulas)
- Click 'Find Next'
- If you need the variable i.e. 'H157', and it is at the end of the existing string, use [End > Shift+Left Arrow > Copy], if not modify as needed.
- End Button, to get to the end of the current reference string
- Type in the new addendum reference
- Paste your variable from step 3
If you then add a loop to the macro, it'll automate the process for you.
If you create the macro and paste the working code here, I'll help with the loop if you want.